1
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Laorenza DW, Mullin KR, Weiss LR, Bayliss SL, Deb P, Awschalom DD, Rondinelli JM, Freedman DE. Coherent spin-control of S = 1 vanadium and molybdenum complexes. Chem Sci 2024:d4sc03107e. [PMID: 39144462 PMCID: PMC11318652 DOI: 10.1039/d4sc03107e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Accepted: 07/25/2024] [Indexed: 08/16/2024] Open
Abstract
The burgeoning field of quantum sensing hinges on the creation and control of quantum bits. To date, the most well-studied quantum sensors are optically active, paramagnetic defects residing in crystalline hosts. We previously developed analogous optically addressable molecules featuring a ground-state spin-triplet centered on a Cr4+ ion with an optical-spin interface. In this work, we evaluate isovalent V3+ and Mo4+ congeners, which offer unique advantages, such as an intrinsic nuclear spin for V3+ or larger spin-orbit coupling for Mo4+, as optically addressable spin systems. We assess the ground-state spin structure and dynamics for each complex, illustrating that all of these spin-triplet species can be coherently controlled. However, unlike the Cr4+ derivatives, these pseudo-tetrahedral V3+ and Mo4+ complexes exhibit no measurable emission. Coupling absorption spectroscopy with computational predictions, we investigate why these complexes exhibit no detectable photoluminescence. These cumulative results suggest that design of future V3+ complexes should target pseudo-tetrahedral symmetries using bidentate or tridentate ligand scaffolds, ideally with deuterated or fluorinated ligand environments. We also suggest that spin-triplet Mo4+, and by extension W4+, complexes may not be suitable candidate optically addressable qubit systems due to their low energy spin-singlet states. By understanding the failures and successes of these systems, we outline additional design features for optically addressable V- or Mo-based molecules to expand the library of tailor-made quantum sensors.
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Affiliation(s)
- Daniel W Laorenza
- Department of Chemistry, Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA
| | - Kathleen R Mullin
- Department of Materials Science and Engineering, Northwestern University Evanston Illinois 60208 USA
| | - Leah R Weiss
- Pritzker School of Molecular Engineering, University of Chicago Chicago Illinois 60637 USA
- Advanced Institute for Materials Research (AIMR-WPI), Tohoku University Sendai 980-8577 Japan
| | - Sam L Bayliss
- Pritzker School of Molecular Engineering, University of Chicago Chicago Illinois 60637 USA
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Pratiti Deb
- Pritzker School of Molecular Engineering, University of Chicago Chicago Illinois 60637 USA
- Department of Physics, University of Chicago Chicago Illinois 60637 USA
| | - David D Awschalom
- Pritzker School of Molecular Engineering, University of Chicago Chicago Illinois 60637 USA
- Department of Physics, University of Chicago Chicago Illinois 60637 USA
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory Lemont Illinois 60439 USA
| | - James M Rondinelli
- Department of Materials Science and Engineering, Northwestern University Evanston Illinois 60208 USA
| | - Danna E Freedman
- Department of Chemistry, Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA
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2
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Li S, Sun Z, McLaughlin NJ, Sharmin A, Agarwal N, Huang M, Sung SH, Lu H, Yan S, Lei H, Hovden R, Wang H, Chen H, Zhao L, Du CR. Observation of stacking engineered magnetic phase transitions within moiré supercells of twisted van der Waals magnets. Nat Commun 2024; 15:5712. [PMID: 38977692 PMCID: PMC11231268 DOI: 10.1038/s41467-024-49942-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 06/26/2024] [Indexed: 07/10/2024] Open
Abstract
Recent demonstrations of moiré magnetism, featuring exotic phases with noncollinear spin order in the twisted van der Waals (vdW) magnet chromium triiodide CrI3, have highlighted the potential of twist engineering of magnetic (vdW) materials. However, the local magnetic interactions, spin dynamics, and magnetic phase transitions within and across individual moiré supercells remain elusive. Taking advantage of a scanning single-spin magnetometry platform, here we report observation of two distinct magnetic phase transitions with separate critical temperatures within a moiré supercell of small-angle twisted double trilayer CrI3. By measuring temperature-dependent spin fluctuations at the coexisting ferromagnetic and antiferromagnetic regions in twisted CrI3, we explicitly show that the Curie temperature of the ferromagnetic state is higher than the Néel temperature of the antiferromagnetic one by ~10 K. Our mean-field calculations attribute such a spatial and thermodynamic phase separation to the stacking order modulated interlayer exchange coupling at the twisted interface of moiré superlattices.
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Affiliation(s)
- Senlei Li
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Zeliang Sun
- Department of Physics, the University of Michigan, Ann Arbor, MI, 48109, USA
| | - Nathan J McLaughlin
- Department of Physics, University of California, San Diego, La Jolla, San Diego, CA, 92093, USA
| | - Afsana Sharmin
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
| | - Nishkarsh Agarwal
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Mengqi Huang
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Suk Hyun Sung
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hanyi Lu
- Department of Physics, University of California, San Diego, La Jolla, San Diego, CA, 92093, USA
| | - Shaohua Yan
- Department of Physics, Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices, Renmin University of China, Beijing, 100872, China
- Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing, 100872, China
| | - Hechang Lei
- Department of Physics, Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices, Renmin University of China, Beijing, 100872, China
- Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing, 100872, China
| | - Robert Hovden
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hailong Wang
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Hua Chen
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
- School of Advanced Materials Discovery, Colorado State University, Fort Collins, CO, 80523, USA
| | - Liuyan Zhao
- Department of Physics, the University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Chunhui Rita Du
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
- Department of Physics, University of California, San Diego, La Jolla, San Diego, CA, 92093, USA.
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3
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Bian K, Zheng W, Chen X, Zhang S, Stöhr R, Denisenko A, Yang S, Wrachtrup J, Jiang Y. A scanning probe microscope compatible with quantum sensing at ambient conditions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:053707. [PMID: 38819258 DOI: 10.1063/5.0202756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 05/08/2024] [Indexed: 06/01/2024]
Abstract
We designed and built up a new type of ambient scanning probe microscope (SPM), which is fully compatible with state-of-the-art quantum sensing technology based on the nitrogen-vacancy (NV) centers in diamond. We chose a qPlus-type tuning fork (Q up to ∼4400) as the current/force sensor of SPM for its high stiffness and stability under various environments, which yields atomic resolution under scanning tunneling microscopy mode and 1.2-nm resolution under atomic force microscopy mode. The tip of SPM can be used to directly image the topography of nanoscale targets on diamond surfaces for quantum sensing and to manipulate the electrostatic environment of NV centers to enhance their sensitivity up to a single proton spin. In addition, we also demonstrated scanning magnetometry and electrometry with a spatial resolution of ∼20 nm. Our new system not only paves the way for integrating atomic/molecular-scale color-center qubits onto SPM tips to produce quantum tips but also provides the possibility of fabricating color-center qubits with nanoscale or atomic precision.
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Affiliation(s)
- Ke Bian
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Wentian Zheng
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Xiakun Chen
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Shichen Zhang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Rainer Stöhr
- Third Institute of Physics, University of Stuttgart and Institute for Quantum Science and Technology (IQST), Stuttgart 70569, Germany
- Max Planck Institute for Solid State Research, Stuttgart 70569, Germany
| | - Andrej Denisenko
- Third Institute of Physics, University of Stuttgart and Institute for Quantum Science and Technology (IQST), Stuttgart 70569, Germany
- Max Planck Institute for Solid State Research, Stuttgart 70569, Germany
| | - Sen Yang
- Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
| | - Jörg Wrachtrup
- Third Institute of Physics, University of Stuttgart and Institute for Quantum Science and Technology (IQST), Stuttgart 70569, Germany
- Max Planck Institute for Solid State Research, Stuttgart 70569, Germany
| | - Ying Jiang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
- New Cornerstone Science Laboratory, Peking University, Beijing 100871, China
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4
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Zhong C, Wang Y, Mai D, Ye C, Li X, Wang H, Dai R, Wang Z, Sun X, Zhang Z. High Spatial Resolution 2D Imaging of Current Density and Pressure for Graphene Devices under High Pressure Using Nitrogen-Vacancy Centers in Diamond. NANO LETTERS 2024. [PMID: 38619219 DOI: 10.1021/acs.nanolett.4c00780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Current density imaging is helpful for discovering interesting electronic phenomena and understanding carrier dynamics, and by combining pressure distributions, several pressure-induced novel physics may be comprehended. In this work, noninvasive, high-resolution two-dimensional images of the current density and pressure gradient for graphene ribbon and hBN-graphene-hBN devices are explored using nitrogen-vacancy (NV) centers in diamond under high pressure. The two-dimensional vector current density is reconstructed by the vector magnetic field mapped by the near-surface NV center layer in the diamond. The current density images accurately and clearly reproduce the complicated structure and current flow of graphene under high pressure. Additionally, the spatial distribution of the pressure is simultaneously mapped, rationalizing the nonuniformity of the current density under high pressure. The current method opens a significant new avenue to investigate electronic transport and conductance variations in two-dimensional materials and electrical devices under high pressure as well as for nondestructive evaluation of semiconductor circuits.
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Affiliation(s)
- Cheng Zhong
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yupeng Wang
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Di Mai
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Chunhui Ye
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiangdong Li
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - He Wang
- Deep Space Exploration Laboratory/Department of Physics, School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Rucheng Dai
- Deep Space Exploration Laboratory/The Centre for Physical Experiments, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhongping Wang
- The Centre for Physical Experiments, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiaoyu Sun
- The Centre for Physical Experiments, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zengming Zhang
- Deep Space Exploration Laboratory/The Centre for Physical Experiments, University of Science and Technology of China, Hefei, Anhui 230026, China
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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5
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Patel AA, Lunts P, Sachdev S. Localization of overdamped bosonic modes and transport in strange metals. Proc Natl Acad Sci U S A 2024; 121:e2402052121. [PMID: 38551843 PMCID: PMC10998611 DOI: 10.1073/pnas.2402052121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 02/28/2024] [Indexed: 04/08/2024] Open
Abstract
The strange metal phase of correlated electrons materials was described in a recent theory by a model of a Fermi surface coupled a two-dimensional quantum critical bosonic field with a spatially random Yukawa coupling. With the assumption of self-averaging randomness, similar to that in the Sachdev-Ye-Kitaev model, numerous observed properties of a strange metal were obtained for a wide range of intermediate temperatures, including the linear in temperature resistivity. The Harris criterion implies that spatial fluctuations in the local position of the critical point must dominate at lower temperatures. For an [Formula: see text]-component boson with [Formula: see text], we use multiple graphics processing units (GPUs) to compute the real frequency spectrum of the boson propagator in a self-consistent mean-field treatment of the boson self-interactions, but an exact treatment of multiple realizations of the spatial randomness from the random boson mass. We find that Landau damping from the fermions leads to the emergence of the physics of the random transverse-field Ising model at low temperatures, as has been proposed by Hoyos, Kotabage, and Vojta. This regime is controlled by localized overdamped eigenmodes of the bosonic scalar field, also has a resistivity which is nearly linear-in-temperature, and extends into a "quantum critical phase" away from the quantum critical point, as observed in several cuprates. For the [Formula: see text] Ising scalar, the mean-field treatment is not applicable, and so we use Hybrid Monte Carlo simulations running on multiple GPUs; we find a rounded transition and localization physics, with strange metal behavior in an extended region around the transition.
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Affiliation(s)
- Aavishkar A. Patel
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY10010
| | - Peter Lunts
- Department of Physics, Harvard University, Cambridge, MA02138
| | - Subir Sachdev
- Department of Physics, Harvard University, Cambridge, MA02138
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6
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Ma MQ, Wu YK, Liu ZW, Zang HX, Shan LK, Jiang W, Liu Y, Ren XF, Chen XD, Guo GC, Sun FW. Integrated Manipulation and Addressing of Spin Defect in Diamond. NANO LETTERS 2024; 24:1660-1666. [PMID: 38266180 DOI: 10.1021/acs.nanolett.3c04376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Scalable and addressable integrated manipulation of qubits is crucial for practical quantum information applications. Different waveguides have been used to transport the optical and electrical driving pulses, which are usually required for qubit manipulation. However, the separated multifields may limit the compactness and efficiency of manipulation and introduce unwanted perturbation. Here, we develop a tapered fiber-nanowire-electrode hybrid structure to realize integrated optical and microwave manipulation of solid-state spins at nanoscale. Visible light and microwave driving pulses are simultaneously transported and concentrated along an Ag nanowire. Studied with spin defects in diamond, the results show that the different driving fields are aligned with high accuracy. The spatially selective spin manipulation is realized. And the frequency-scanning optically detected magnetic resonance (ODMR) of spin qubits is measured, illustrating the potential for portable quantum sensing. Our work provides a new scheme for developing compact, miniaturized quantum sensors and quantum information processing devices.
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Affiliation(s)
- Meng-Qi Ma
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Yun-Kun Wu
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Zhi-Wei Liu
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Han-Xiang Zang
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Long-Kun Shan
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Wang Jiang
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Yong Liu
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
| | - Xi-Feng Ren
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, People's Republic of China
| | - Xiang-Dong Chen
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, People's Republic of China
| | - Guang-Can Guo
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, People's Republic of China
| | - Fang-Wen Sun
- CAS Key Laboratory of Quantum Information, School of Physical Sciences,University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, People's Republic of China
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7
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Liang K, Zhu M, Qin X, Meng Z, Wang P, Du J. Field-programmable-gate-array based hardware platform for nitrogen-vacancy center based fast magnetic imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:024701. [PMID: 38341725 DOI: 10.1063/5.0187228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 01/18/2024] [Indexed: 02/13/2024]
Abstract
A nitrogen-vacancy center based scanning magnetic microscope can be used to characterize magnetics at the nanoscale with high sensitivity. This paper reports a field-programmable-gate-array based hardware system that is designed to realize control and signal readout for fast scanning magnetic imaging with a nitrogen-vacancy center. A 10-channel 1 Msps @ 20 bit analog signal generator, a 12-channel 50 ps resolution pulse generator, a 300 Msps @ 16 bit lock-in amplifier with proportional integral derivative control function, and a 4-channel 200 Msps counter are integrated on the platform. A customized acceleration algorithm is realized with the re-configurable field-programmable-gate-array chip to accelerate the imaging speed of the nitrogen-vacancy system, and the experimental results prove that the imaging efficiency can be accelerated by five times compared to the system without the acceleration algorithm. The platform has considerable potential for future applications of fast scanning magnetic imaging.
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Affiliation(s)
- Kaiqing Liang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Mingdong Zhu
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Xi Qin
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Ziqing Meng
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Pengfei Wang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Jiangfeng Du
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
- Institute of Quantum Sensing and School of Physics, Zhejiang University, Hangzhou 310027, China
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8
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Cosme P, Simões D. Feedback enhanced Dyakonov-Shur instability in graphene field-effect transistors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:175301. [PMID: 38241738 DOI: 10.1088/1361-648x/ad20a4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 01/19/2024] [Indexed: 01/21/2024]
Abstract
Graphene devices are known to have the potential to operate THz signals. In particular, graphene field-effect transistors (gFETs) have been proposed as devices to host plasmonic instabilities in the THz realm; for instance, Dyakonov-Shur (DS) instability which relies upon dc excitation. In this work, starting from a hydrodynamical description of the charge carriers, we extend the transmission line description of gFETs to a scheme with a positive feedback loop, also considering the effects of delay, which leads to the transcendental Laplace-transform transfer function, with complex frequencys, with terms of the forme-assechk(s)/s, for a givena∈R0+arising from the delay time and withk∈N. Applying the conditions for the excitation of DS instability, we report an enhanced voltage gain in the linear regime that is corroborated by our simulations of the nonlinear hydrodynamic model for the charge carriers. This translates to both greater saturation amplitude-often up to 50% increase-and faster growth rate of the self-oscillations. Thus, we bring forth a prospective concept for the realization of a THz oscillator suitable for future plasmonic circuitry.
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Affiliation(s)
- Pedro Cosme
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
| | - Diogo Simões
- Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, 1049-001 Lisboa, Portugal
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9
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McLaughlin N, Li S, Brock JA, Zhang S, Lu H, Huang M, Xiao Y, Zhou J, Tserkovnyak Y, Fullerton EE, Wang H, Du CR. Local Control of a Single Nitrogen-Vacancy Center by Nanoscale Engineered Magnetic Domain Wall Motion. ACS NANO 2023; 17:25689-25696. [PMID: 38050827 PMCID: PMC10753891 DOI: 10.1021/acsnano.3c10633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 11/18/2023] [Accepted: 11/28/2023] [Indexed: 12/07/2023]
Abstract
Effective control and readout of qubits form the technical foundation of next-generation, transformative quantum information sciences and technologies. The nitrogen-vacancy (NV) center, an intrinsic three-level spin system, is naturally relevant in this context due to its excellent quantum coherence, high fidelity of operations, and remarkable functionality over a broad range of experimental conditions. It is an active contender for the development and implementation of cutting-edge quantum technologies. Here, we report magnetic domain wall motion driven local control and measurements of the NV spin properties. By engineering the local magnetic field environment of an NV center via nanoscale reconfigurable domain wall motion, we show that NV photoluminescence, spin level energies, and coherence time can be reliably controlled and correlated to the magneto-transport response of a magnetic device. Our results highlight the electrically tunable dipole interaction between NV centers and nanoscale magnetic structures, providing an attractive platform to realize interactive information transfer between spin qubits and nonvolatile magnetic memory in hybrid quantum spintronic systems.
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Affiliation(s)
- Nathan
J. McLaughlin
- Department
of Physics, University of California, San
Diego, La Jolla, California 92093, United States
| | - Senlei Li
- School of
Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jeffrey A. Brock
- Center
for
Memory and Recording Research, University
of California, San Diego, La Jolla, California 92093-0401, United States
| | - Shu Zhang
- Max Planck
Institute for the Physics of Complex Systems, Dresden 01187, Germany
| | - Hanyi Lu
- Department
of Physics, University of California, San
Diego, La Jolla, California 92093, United States
| | - Mengqi Huang
- School of
Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Yuxuan Xiao
- Center
for
Memory and Recording Research, University
of California, San Diego, La Jolla, California 92093-0401, United States
| | - Jingcheng Zhou
- School of
Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Yaroslav Tserkovnyak
- Department
of Physics and Astronomy, University of
California, Los Angeles, California 90095, United States
| | - Eric E. Fullerton
- Center
for
Memory and Recording Research, University
of California, San Diego, La Jolla, California 92093-0401, United States
| | - Hailong Wang
- School of
Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Chunhui Rita Du
- Department
of Physics, University of California, San
Diego, La Jolla, California 92093, United States
- School of
Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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10
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Zhou H, Martin LS, Tyler M, Makarova O, Leitao N, Park H, Lukin MD. Robust Higher-Order Hamiltonian Engineering for Quantum Sensing with Strongly Interacting Systems. PHYSICAL REVIEW LETTERS 2023; 131:220803. [PMID: 38101374 DOI: 10.1103/physrevlett.131.220803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 10/18/2023] [Indexed: 12/17/2023]
Abstract
Dynamical decoupling techniques constitute an integral part of many quantum sensing platforms, often leading to orders-of-magnitude improvements in coherence time and sensitivity. Most ac sensing sequences involve a periodic echolike structure, in which the target signal is synchronized with the echo period. We show that for strongly interacting systems, this construction leads to a fundamental sensitivity limit associated with imperfect interaction decoupling. We present a simple physical picture demonstrating the origin of this limitation, and further formalize these considerations in terms of concise higher-order decoupling rules. We then show how these limitations can be surpassed by identifying a novel sequence building block, in which the signal period matches twice the echo period. Using these decoupling rules and the resulting sequence building block, we experimentally demonstrate significant improvements in dynamical decoupling timescales and magnetic field sensitivity, opening the door for new applications in quantum sensing and quantum many-body physics.
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Affiliation(s)
- Hengyun Zhou
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Leigh S Martin
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Matthew Tyler
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Oksana Makarova
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Nathaniel Leitao
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Hongkun Park
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Mikhail D Lukin
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
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11
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Guillet S, Guiselin B, Boughzala M, Desages V, Bartolo D. Curvature Heterogeneities Act as Singular Perturbations to Smooth Laplacian Fields: A Fluid Mechanics Demonstration. PHYSICAL REVIEW LETTERS 2023; 131:188201. [PMID: 37977613 DOI: 10.1103/physrevlett.131.188201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 10/04/2023] [Indexed: 11/19/2023]
Abstract
In this Letter, we use a model fluid mechanics experiment to elucidate the impact of curvature heterogeneities on two-dimensional fields deriving from harmonic potential functions. This result is directly relevant to explain the smooth stationary structures in physical systems as diverse as curved liquid crystal and magnetic films, heat and Ohmic transport in wrinkled two-dimensional materials, and flows in confined channels. Combining microfluidic experiments and theory, we explain how curvature heterogeneities shape confined viscous flows. We show that isotropic bumps induce local distortions to Darcy's flows, whereas anisotropic curvature heterogeneities disturb them algebraically over system-spanning scales. Thanks to an electrostatic analogy, we gain insight into this singular geometric perturbation, and quantitatively explain it using both conformal mapping and numerical simulations. Altogether, our findings establish the robustness of our experimental observations and their broad relevance to all Laplacian problems beyond the specifics of our fluid mechanics experiment.
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Affiliation(s)
- Stéphane Guillet
- ENSL, CNRS, Laboratoire de physique, Université de Lyon, F-69342 Lyon, France
| | - Benjamin Guiselin
- ENSL, CNRS, Laboratoire de physique, Université de Lyon, F-69342 Lyon, France
| | - Mariem Boughzala
- ENSL, CNRS, Laboratoire de physique, Université de Lyon, F-69342 Lyon, France
| | - Vassili Desages
- ENSL, CNRS, Laboratoire de physique, Université de Lyon, F-69342 Lyon, France
| | - Denis Bartolo
- ENSL, CNRS, Laboratoire de physique, Université de Lyon, F-69342 Lyon, France
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12
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Chen Z, Ding Z, Wang M, Yu P, Yang K, Sun Y, Wang P, Wang Y, Shi F, Bao X, Du J. A convenient and robust design for diamond-based scanning probe microscopes. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:113703. [PMID: 37947500 DOI: 10.1063/5.0174744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023]
Abstract
Nitrogen-vacancy centers in diamond have been developed as a sensitive magnetic sensor and broadly applied on condensed matter physics. We present a design of a scanning probe microscope based on a nitrogen-vacancy center that can operate under various experimental conditions, including a broad temperature range (20-500 K) and a high-vacuum condition (1 × 10-7 mbar). The design of a compact and robust scanning head and vacuum chamber system is presented, which ensures system stability while enabling the convenience of equipment operations. By showcasing the temperature control performance and presenting confocal images of a single-layer graphene and a diamond probe, along with images of a ferromagnetic strip and an epitaxial BiFeO3 film on the SrTiO3 substrate, we demonstrate the reliability of the instrument. Our study proposes a method and a corresponding design for this microscope that extends its potential applications in nanomagnetism and spintronics.
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Affiliation(s)
- Zhousheng Chen
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Zhe Ding
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Mengqi Wang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Pei Yu
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Kai Yang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yumeng Sun
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Pengfei Wang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Ya Wang
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
| | - Fazhan Shi
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
- School of Biomedical Engineering and Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou 215123, China
| | - Xinhe Bao
- Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jiangfeng Du
- CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China
- School of Physics, Zhejiang University, Hangzhou 310027, China
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13
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Barcons Ruiz D, Hesp NC, Herzig Sheinfux H, Ramos Marimón C, Maissen CM, Principi A, Asgari R, Taniguchi T, Watanabe K, Polini M, Hillenbrand R, Torre I, Koppens FH. Experimental signatures of the transition from acoustic plasmon to electronic sound in graphene. SCIENCE ADVANCES 2023; 9:eadi0415. [PMID: 37774035 PMCID: PMC10541005 DOI: 10.1126/sciadv.adi0415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 08/30/2023] [Indexed: 10/01/2023]
Abstract
Fermi liquids respond differently to perturbations depending on whether their frequency is higher (collisionless regime) or lower (hydrodynamic regime) than the interparticle collision rate. This results in a different phase velocity between the collisionless zero sound and the hydrodynamic first sound. We performed terahertz photocurrent nanoscopy measurements on graphene devices, with a metallic gate close to the graphene layer, to probe the dispersion of propagating acoustic plasmons, the counterpart of sound modes in electronic Fermi liquids. We report the observation of a change in the plasmon phase velocity when the excitation frequency approaches the electron-electron collision rate that is compatible with the transition between the zero and the first sound mode.
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Affiliation(s)
- David Barcons Ruiz
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
| | - Niels C.H. Hesp
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
| | - Hanan Herzig Sheinfux
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
| | - Carlos Ramos Marimón
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
| | | | - Alessandro Principi
- Department of Physics and Astronomy, The University of Manchester, M13 9PL Manchester, UK
| | - Reza Asgari
- School of Physics, Institute for Research in Fundamental Sciences, IPM, Tehran 19395-5531, Iran
- School of Physics, University of New South Wales, Kensington, NSW 2052, Australia
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Marco Polini
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
- Dipartimento di Fisica, Università di Pisa, Largo Bruno Pontecorvo 3, I-56127 Pisa, Italy
- Istituto Italiano di Tecnologia, Graphene Labs, Via Morego 30, I-16163 Genova, Italy
| | - Rainer Hillenbrand
- CIC nanoGUNE, 20018 Donostia-San Sebastián, Spain
- CIC nanoGUNE BRTA and Department of Electricity and Electronics, UPV/EHU, 20018 Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Iacopo Torre
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
| | - Frank H.L. Koppens
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain
- ICREA-Institucio Catalana de Recerca i Estudis Avancats, 08010 Barcelona, Spain
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14
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Mayes D, Farahmand F, Grossnickle M, Lohmann M, Aldosary M, Li J, Aji V, Shi J, Song JCW, Gabor NM. Mapping the intrinsic photocurrent streamlines through micromagnetic heterostructure devices. Proc Natl Acad Sci U S A 2023; 120:e2221815120. [PMID: 37722037 PMCID: PMC10523491 DOI: 10.1073/pnas.2221815120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 08/08/2023] [Indexed: 09/20/2023] Open
Abstract
Photocurrent in quantum materials is often collected at global contacts far away from the initial photoexcitation. This collection process is highly nonlocal. It involves an intricate spatial pattern of photocurrent flow (streamlines) away from its primary photoexcitation that depends sensitively on the configuration of current collecting contacts as well as the spatial nonuniformity and tensor structure of conductivity. Direct imaging to track photocurrent streamlines is challenging. Here, we demonstrate a microscopy method to image photocurrent streamlines through ultrathin heterostructure devices comprising platinum on yttrium iron garnet (YIG). We accomplish this by combining scanning photovoltage microscopy with a uniform rotating magnetic field. Here, local photocurrent is generated through a photo-Nernst type effect with its direction controlled by the external magnetic field. This enables the mapping of photocurrent streamlines in a variety of geometries that include conventional Hall bar-type devices, but also unconventional wing-shaped devices called electrofoils. In these, we find that photocurrent streamlines display contortion, compression, and expansion behavior depending on the shape and angle of attack of the electrofoil devices, much in the same way as tracers in a wind tunnel map the flow of air around an aerodynamic airfoil. This affords a powerful tool to visualize and characterize charge flow in optoelectronic devices.
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Affiliation(s)
- David Mayes
- Department of Physics and Astronomy, University of California, Riverside, CA92521
- Laboratory of Quantum Materials Optoelectronics, University of California, Riverside, CA92521
| | - Farima Farahmand
- Department of Physics and Astronomy, University of California, Riverside, CA92521
- Laboratory of Quantum Materials Optoelectronics, University of California, Riverside, CA92521
| | - Maxwell Grossnickle
- Department of Physics and Astronomy, University of California, Riverside, CA92521
- Laboratory of Quantum Materials Optoelectronics, University of California, Riverside, CA92521
| | - Mark Lohmann
- Department of Physics and Astronomy, University of California, Riverside, CA92521
| | - Mohammed Aldosary
- Department of Physics and Astronomy, University of California, Riverside, CA92521
| | - Junxue Li
- Department of Physics and Astronomy, University of California, Riverside, CA92521
| | - Vivek Aji
- Department of Physics and Astronomy, University of California, Riverside, CA92521
| | - Jing Shi
- Department of Physics and Astronomy, University of California, Riverside, CA92521
| | - Justin C. W. Song
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore637371, Singapore
| | - Nathaniel M. Gabor
- Department of Physics and Astronomy, University of California, Riverside, CA92521
- Laboratory of Quantum Materials Optoelectronics, University of California, Riverside, CA92521
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15
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Greenwood G, Kim JM, Nahid SM, Lee Y, Hajarian A, Nam S, Espinosa-Marzal RM. Dynamically tuning friction at the graphene interface using the field effect. Nat Commun 2023; 14:5801. [PMID: 37726306 PMCID: PMC10509204 DOI: 10.1038/s41467-023-41375-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 09/01/2023] [Indexed: 09/21/2023] Open
Abstract
Dynamically controlling friction in micro- and nanoscale devices is possible using applied electrical bias between contacting surfaces, but this can also induce unwanted reactions which can affect device performance. External electric fields provide a way around this limitation by removing the need to apply bias directly between the contacting surfaces. 2D materials are promising candidates for this approach as their properties can be easily tuned by electric fields and they can be straightforwardly used as surface coatings. This work investigates the friction between single layer graphene and an atomic force microscope tip under the influence of external electric fields. While the primary effect in most systems is electrostatically controllable adhesion, graphene in contact with semiconducting tips exhibits a regime of unexpectedly enhanced and highly tunable friction. The origins of this phenomenon are discussed in the context of fundamental frictional dissipation mechanisms considering stick slip behavior, electron-phonon coupling and viscous electronic flow.
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Affiliation(s)
- Gus Greenwood
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Jin Myung Kim
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - Shahriar Muhammad Nahid
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yeageun Lee
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Amin Hajarian
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - SungWoo Nam
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - Rosa M Espinosa-Marzal
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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16
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Huang M, Green JC, Zhou J, Williams V, Li S, Lu H, Djugba D, Wang H, Flebus B, Ni N, Du CR. Layer-Dependent Magnetism and Spin Fluctuations in Atomically Thin van der Waals Magnet CrPS 4. NANO LETTERS 2023; 23:8099-8105. [PMID: 37656017 DOI: 10.1021/acs.nanolett.3c02129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
van der Waals (vdW) magnets, an emerging family of two-dimensional (2D) materials, have received tremendous attention due to their rich fundamental physics and significant potential for cutting-edge technological applications. In contrast to the conventional bulk counterparts, vdW magnets exhibit significant tunability of local material properties, such as stacking engineered interlayer coupling and layer-number dependent magnetic and electronic interactions, which promise to deliver previously unavailable merits to develop multifunctional microelectronic devices. As a further ingredient of this emerging topic, here we report nanoscale quantum sensing and imaging of the atomically thin vdW magnet chromium thiophosphate CrPS4, revealing its characteristic layer-dependent 2D static magnetism and dynamic spin fluctuations. We also show a large tunneling magnetoresistance in CrPS4-based spin filter vdW heterostructures. The excellent material stability and robust strategy against environmental degradation in combination with tailored magnetic properties highlight the potential of CrPS4 in developing state-of-the-art 2D spintronic devices for next-generation information technologies.
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Affiliation(s)
- Mengqi Huang
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jazmine C Green
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Jingcheng Zhou
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Violet Williams
- Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Senlei Li
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Hanyi Lu
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
| | - Dziga Djugba
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Hailong Wang
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Benedetta Flebus
- Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Ni Ni
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Chunhui Rita Du
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093, United States
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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17
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Huang M, Sun Z, Yan G, Xie H, Agarwal N, Ye G, Sung SH, Lu H, Zhou J, Yan S, Tian S, Lei H, Hovden R, He R, Wang H, Zhao L, Du CR. Revealing intrinsic domains and fluctuations of moiré magnetism by a wide-field quantum microscope. Nat Commun 2023; 14:5259. [PMID: 37644000 PMCID: PMC10465594 DOI: 10.1038/s41467-023-40543-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 08/01/2023] [Indexed: 08/31/2023] Open
Abstract
Moiré magnetism featured by stacking engineered atomic registry and lattice interactions has recently emerged as an appealing quantum state of matter at the forefront of condensed matter physics research. Nanoscale imaging of moiré magnets is highly desirable and serves as a prerequisite to investigate a broad range of intriguing physics underlying the interplay between topology, electronic correlations, and unconventional nanomagnetism. Here we report spin defect-based wide-field imaging of magnetic domains and spin fluctuations in twisted double trilayer (tDT) chromium triiodide CrI3. We explicitly show that intrinsic moiré domains of opposite magnetizations appear over arrays of moiré supercells in low-twist-angle tDT CrI3. In contrast, spin fluctuations measured in tDT CrI3 manifest little spatial variations on the same mesoscopic length scale due to the dominant driving force of intralayer exchange interaction. Our results enrich the current understanding of exotic magnetic phases sustained by moiré magnetism and highlight the opportunities provided by quantum spin sensors in probing microscopic spin related phenomena on two-dimensional flatland.
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Affiliation(s)
- Mengqi Huang
- Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Zeliang Sun
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Gerald Yan
- Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Hongchao Xie
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Nishkarsh Agarwal
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Gaihua Ye
- Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX, 79409, USA
| | - Suk Hyun Sung
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hanyi Lu
- Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Jingcheng Zhou
- Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Shaohua Yan
- Laboratory for Neutron Scattering, and Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices, Department of Physics, Renmin University of China, Beijing, 100872, China
| | - Shangjie Tian
- Laboratory for Neutron Scattering, and Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices, Department of Physics, Renmin University of China, Beijing, 100872, China
- School of Materials Science and Engineering, Anhui University, Hefei, 230601, China
| | - Hechang Lei
- Laboratory for Neutron Scattering, and Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices, Department of Physics, Renmin University of China, Beijing, 100872, China
| | - Robert Hovden
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Rui He
- Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX, 79409, USA
| | - Hailong Wang
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Liuyan Zhao
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Chunhui Rita Du
- Department of Physics, University of California, San Diego, La Jolla, CA, 92093, USA.
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, CA, 92093, USA.
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18
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Vijayakrishnan S, Poitevin F, Yu O, Berkson-Korenberg Z, Petrescu M, Lilly MP, Szkopek T, Agarwal K, West KW, Pfeiffer LN, Gervais G. Anomalous electronic transport in high-mobility Corbino rings. Nat Commun 2023; 14:3906. [PMID: 37400458 DOI: 10.1038/s41467-023-39526-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/19/2023] [Indexed: 07/05/2023] Open
Abstract
We report low-temperature electronic transport measurements performed in two multi-terminal Corbino samples formed in GaAs/Al-GaAs two-dimensional electron gases (2DEG) with both ultra-high electron mobility ( ≳ 20 × 106 cm2/ Vs) and with distinct electron density of 1.7 and 3.6 × 1011 cm-2. In both Corbino samples, a non-monotonic behavior is observed in the temperature dependence of the resistance below 1 K. Surprisingly, a sharp decrease in resistance is observed with increasing temperature in the sample with lower electron density, whereas an opposite behavior is observed in the sample with higher density. To investigate further, transport measurements were performed in large van der Pauw samples having identical heterostructures, and as expected they exhibit resistivity that is monotonic with temperature. Finally, we discuss the results in terms of various lengthscales leading to ballistic and hydrodynamic electronic transport, as well as a possible Gurzhi effect.
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Affiliation(s)
| | - F Poitevin
- Department of Physics, McGill University, Montréal, Québec, Canada
| | - Oulin Yu
- Department of Physics, McGill University, Montréal, Québec, Canada
| | | | - M Petrescu
- Department of Physics, McGill University, Montréal, Québec, Canada
| | - M P Lilly
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, NM, USA
| | - T Szkopek
- Department of Electrical and Computer Engineering, McGill University, Montréal, Québec, Canada
| | - Kartiek Agarwal
- Department of Physics, McGill University, Montréal, Québec, Canada
| | - K W West
- Department of Electrical Engineering, Princeton University, Princeton, NJ, USA
| | - L N Pfeiffer
- Department of Electrical Engineering, Princeton University, Princeton, NJ, USA
| | - G Gervais
- Department of Physics, McGill University, Montréal, Québec, Canada.
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19
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Hui A, Skinner B. Current Noise of Hydrodynamic Electrons. PHYSICAL REVIEW LETTERS 2023; 130:256301. [PMID: 37418728 DOI: 10.1103/physrevlett.130.256301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 05/04/2023] [Indexed: 07/09/2023]
Abstract
A resistor at finite temperature produces white noise fluctuations of the current called Johnson-Nyquist noise. Measuring the amplitude of this noise provides a powerful primary thermometry technique to access the electron temperature. In practical situations, however, one needs to generalize the Johnson-Nyquist theorem to handle spatially inhomogeneous temperature profiles. Recent work provided such a generalization for Ohmic devices obeying the Wiedemann-Franz law, but there is a need to provide a similar generalization for hydrodynamic electron systems, since hydrodynamic electrons provide unusual sensitivity for Johnson noise thermometry but they do not admit a local conductivity nor obey the Wiedemann-Franz law. Here we address this need by considering low-frequency Johnson noise in the hydrodynamic setting for a rectangular geometry. Unlike in the Ohmic setting, we find that the Johnson noise is geometry dependent due to nonlocal viscous gradients. Nonetheless, ignoring the geometric correction only leads to an error of at most 40% as compared to naively using the Ohmic result.
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Affiliation(s)
- Aaron Hui
- Department of Physics, Ohio State University, Columbus, Ohio 43202, USA
| | - Brian Skinner
- Department of Physics, Ohio State University, Columbus, Ohio 43202, USA
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20
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Wolf Y, Aharon-Steinberg A, Yan B, Holder T. Para-hydrodynamics from weak surface scattering in ultraclean thin flakes. Nat Commun 2023; 14:2334. [PMID: 37087462 PMCID: PMC10122658 DOI: 10.1038/s41467-023-37966-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 03/27/2023] [Indexed: 04/24/2023] Open
Abstract
Electron hydrodynamics typically emerges in electron fluids with a high electron-electron collision rate. However, new experiments with thin flakes of WTe2 have revealed that other momentum-conserving scattering processes can replace the role of the electron-electron interaction, thereby leading to a novel, so-called para-hydrodynamic regime. Here, we develop the kinetic theory for para-hydrodynamic transport. To this end, we consider a ballistic electron gas in a thin three-dimensional sheet where the momentum-relaxing (lmr) and momentum-conserving (lmc) mean free paths are decreased due to boundary scattering from a rough surface. The resulting effective mean free path of the in-plane components of the electronic flow is then expressed in terms of microscopic parameters of the sheet boundaries, predicting that a para-hydrodynamic regime with lmr ≫ lmc emerges generically in ultraclean three-dimensional materials. Using our approach, we recover the transport properties of WTe2 in the para-hydrodynamic regime in good agreement with existing experiments.
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Affiliation(s)
- Yotam Wolf
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Amit Aharon-Steinberg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Binghai Yan
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Tobias Holder
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel.
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21
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Xin N, Lourembam J, Kumaravadivel P, Kazantsev AE, Wu Z, Mullan C, Barrier J, Geim AA, Grigorieva IV, Mishchenko A, Principi A, Fal'ko VI, Ponomarenko LA, Geim AK, Berdyugin AI. Giant magnetoresistance of Dirac plasma in high-mobility graphene. Nature 2023; 616:270-274. [PMID: 37045919 PMCID: PMC10097601 DOI: 10.1038/s41586-023-05807-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 02/08/2023] [Indexed: 04/14/2023]
Abstract
The most recognizable feature of graphene's electronic spectrum is its Dirac point, around which interesting phenomena tend to cluster. At low temperatures, the intrinsic behaviour in this regime is often obscured by charge inhomogeneity1,2 but thermal excitations can overcome the disorder at elevated temperatures and create an electron-hole plasma of Dirac fermions. The Dirac plasma has been found to exhibit unusual properties, including quantum-critical scattering3-5 and hydrodynamic flow6-8. However, little is known about the plasma's behaviour in magnetic fields. Here we report magnetotransport in this quantum-critical regime. In low fields, the plasma exhibits giant parabolic magnetoresistivity reaching more than 100 per cent in a magnetic field of 0.1 tesla at room temperature. This is orders-of-magnitude higher than magnetoresistivity found in any other system at such temperatures. We show that this behaviour is unique to monolayer graphene, being underpinned by its massless spectrum and ultrahigh mobility, despite frequent (Planckian limit) scattering3-5,9-14. With the onset of Landau quantization in a magnetic field of a few tesla, where the electron-hole plasma resides entirely on the zeroth Landau level, giant linear magnetoresistivity emerges. It is nearly independent of temperature and can be suppressed by proximity screening15, indicating a many-body origin. Clear parallels with magnetotransport in strange metals12-14 and so-called quantum linear magnetoresistance predicted for Weyl metals16 offer an interesting opportunity to further explore relevant physics using this well defined quantum-critical two-dimensional system.
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Affiliation(s)
- Na Xin
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
- National Graphene Institute, University of Manchester, Manchester, UK
| | - James Lourembam
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - Piranavan Kumaravadivel
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
- National Graphene Institute, University of Manchester, Manchester, UK
| | - A E Kazantsev
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - Zefei Wu
- National Graphene Institute, University of Manchester, Manchester, UK
| | - Ciaran Mullan
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - Julien Barrier
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
- National Graphene Institute, University of Manchester, Manchester, UK
| | - Alexandra A Geim
- National Graphene Institute, University of Manchester, Manchester, UK
| | - I V Grigorieva
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - A Mishchenko
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - A Principi
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
| | - V I Fal'ko
- Department of Physics and Astronomy, University of Manchester, Manchester, UK
- National Graphene Institute, University of Manchester, Manchester, UK
| | - L A Ponomarenko
- Department of Physics, University of Lancaster, Lancaster, UK.
| | - A K Geim
- Department of Physics and Astronomy, University of Manchester, Manchester, UK.
- National Graphene Institute, University of Manchester, Manchester, UK.
- Department of Materials Science and Engineering, National University of Singapore, Singapore, Singapore.
| | - Alexey I Berdyugin
- Department of Physics and Astronomy, University of Manchester, Manchester, UK.
- National Graphene Institute, University of Manchester, Manchester, UK.
- Department of Materials Science and Engineering, National University of Singapore, Singapore, Singapore.
- Department of Physics, National University of Singapore, Singapore, Singapore.
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22
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Choi YG, Doan MH, Ngoc LLP, Lee J, Choi GM, Chernodub MN. Pseudo-Hydrodynamic Flow of Quasiparticles in Semimetal WTe 2 at Room Temperature. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2206604. [PMID: 36960494 DOI: 10.1002/smll.202206604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 02/28/2023] [Indexed: 06/18/2023]
Abstract
Recently, much interest has emerged in fluid-like electric charge transport in various solid-state systems. The hydrodynamic behavior of the electronic fluid reveals itself as a decrease of the electrical resistance with increasing temperature (the Gurzhi effect) in narrow channels, polynomial scaling of the resistance as a function of the channel width, violation of the Wiedemann-Franz law supported by the emergence of the Poiseuille flow. Similar to whirlpools in flowing water, the viscous electronic flow generates vortices, resulting in abnormal sign-changing electrical response driven by backflow. However, the question of whether the long-ranged sign-changing electrical response can be produced by a mechanism other than hydrodynamics has not been addressed so far. Here polarization-sensitive laser microscopy is used to demonstrate the emergence of visually similar abnormal sign-alternating patterns in semi-metallic tungsten ditelluride at room temperature where this material does not exhibit true hydrodynamics. It is found that the neutral quasiparticle current consisting of electrons and holes obeys an equation remarkably similar to the Navier-Stokes equation. In particular, the momentum relaxation is replaced by the much slower process of quasiparticle recombination. This pseudo-hydrodynamic flow of quasiparticles leads to a sign-changing charge accumulation pattern via different diffusivities of electrons and holes.
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Affiliation(s)
- Young-Gwan Choi
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Manh-Ha Doan
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea
- Department of Physics, Technical University of Denmark, Kgs. Lyngby, Copenhagen, 2800, Denmark
| | - Luu Ly Pham Ngoc
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Junsu Lee
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea
| | - Gyung-Min Choi
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Suwon, 16419, South Korea
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23
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Zhao M, Lin Q, Meng Q, Shan W, Zhu L, Chen Y, Liu T, Zhao L, Jiang Z. All Fiber Vector Magnetometer Based on Nitrogen-Vacancy Center. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:949. [PMID: 36903827 PMCID: PMC10005582 DOI: 10.3390/nano13050949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/26/2023] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Magnetometers based on nitrogen-vacancy (NV) centers in diamonds have promising applications in fields of living systems biology, condensed matter physics, and industry. This paper proposes a portable and flexible all-fiber NV center vector magnetometer by using fibers to substitute all conventional spatial optical elements, realizing laser excitation and fluorescence collection of micro-diamond with multi-mode fibers simultaneously and efficiently. An optical model is established to investigate multi-mode fiber interrogation of micro-diamond to estimate the optical performance of NV center system. A new analysis method is proposed to extract the magnitude and direction of the magnetic field, combining the morphology of the micro-diamond, thus realizing μm-scale vector magnetic field detection at the tip of the fiber probe. Experimental testing shows our fabricated magnetometer has a sensitivity of 0.73 nT/Hz1/2, demonstrating its feasibility and performance in comparison with conventional confocal NV center magnetometers. This research presents a robust and compact magnetic endoscopy and remote-magnetic measurement approach, which will substantially promote the practical application of magnetometers based on NV centers.
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Affiliation(s)
- Man Zhao
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Qijing Lin
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- Collaborative Innovation Center of High-End Manufacturing Equipment, Xi’an Jiaotong University, Xi’an 710054, China
- Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing, Yantai 265503, China
- Xi’an Jiaotong University (Yantai) Research Institute for Intelligent Sensing Technology and System, Xi’an Jiaotong University, Xi’an 710049, China
| | - Qingzhi Meng
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Wenjun Shan
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Liangquan Zhu
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yao Chen
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Tao Liu
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Libo Zhao
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
- Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing, Yantai 265503, China
- Xi’an Jiaotong University (Yantai) Research Institute for Intelligent Sensing Technology and System, Xi’an Jiaotong University, Xi’an 710049, China
| | - Zhuangde Jiang
- State Key Laboratory of Mechanical Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, China
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24
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Krebs ZJ, Behn WA, Li S, Smith KJ, Watanabe K, Taniguchi T, Levchenko A, Brar VW. Imaging the breaking of electrostatic dams in graphene for ballistic and viscous fluids. Science 2023; 379:671-676. [PMID: 36795831 DOI: 10.1126/science.abm6073] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The charge carriers in a material can, under special circumstances, behave as a viscous fluid. In this work, we investigated such behavior by using scanning tunneling potentiometry to probe the nanometer-scale flow of electron fluids in graphene as they pass through channels defined by smooth and tunable in-plane p-n junction barriers. We observed that as the sample temperature and channel widths are increased, the electron fluid flow undergoes a Knudsen-to-Gurzhi transition from the ballistic to the viscous regime characterized by a channel conductance that exceeds the ballistic limit, as well as suppressed charge accumulation against the barriers. Our results are well modeled by finite element simulations of two-dimensional viscous current flow, and they illustrate how Fermi liquid flow evolves with carrier density, channel width, and temperature.
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Affiliation(s)
- Zachary J Krebs
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Wyatt A Behn
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Songci Li
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Keenan J Smith
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
| | - Alex Levchenko
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Victor W Brar
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
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25
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Observation of hydrodynamic plasmons and energy waves in graphene. Nature 2023; 614:688-693. [PMID: 36813893 DOI: 10.1038/s41586-022-05619-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 12/02/2022] [Indexed: 02/24/2023]
Abstract
Thermally excited electrons and holes form a quantum-critical Dirac fluid in ultraclean graphene and their electrodynamic responses are described by a universal hydrodynamic theory. The hydrodynamic Dirac fluid can host intriguing collective excitations distinctively different from those in a Fermi liquid1-4. Here we report the observation of the hydrodynamic plasmon and energy wave in ultraclean graphene. We use the on-chip terahertz (THz) spectroscopy technique to measure the THz absorption spectra of a graphene microribbon as well as the propagation of the energy wave in graphene close to charge neutrality. We observe a prominent high-frequency hydrodynamic bipolar-plasmon resonance and a weaker low-frequency energy-wave resonance of the Dirac fluid in ultraclean graphene. The hydrodynamic bipolar plasmon is characterized by the antiphase oscillation of massless electrons and holes in graphene. The hydrodynamic energy wave is an electron-hole sound mode with both charge carriers oscillating in phase and moving together. The spatial-temporal imaging technique shows that the energy wave propagates at a characteristic speed of [Formula: see text] near the charge neutrality2-4. Our observations open new opportunities to explore collective hydrodynamic excitations in graphene systems.
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26
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Broadband microwave detection using electron spins in a hybrid diamond-magnet sensor chip. Nat Commun 2023; 14:490. [PMID: 36717574 PMCID: PMC9887009 DOI: 10.1038/s41467-023-36146-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/18/2023] [Indexed: 01/31/2023] Open
Abstract
Quantum sensing has developed into a main branch of quantum science and technology. It aims at measuring physical quantities with high resolution, sensitivity, and dynamic range. Electron spins in diamond are powerful magnetic field sensors, but their sensitivity in the microwave regime is limited to a narrow band around their resonance frequency. Here, we realize broadband microwave detection using spins in diamond interfaced with a thin-film magnet. A pump field locally converts target microwave signals to the sensor-spin frequency via the non-linear spin-wave dynamics of the magnet. Two complementary conversion protocols enable sensing and high-fidelity spin control over a gigahertz bandwidth, allowing characterization of the spin-wave band at multiple gigahertz above the sensor-spin frequency. The pump-tunable, hybrid diamond-magnet sensor chip opens the way for spin-based gigahertz material characterizations at small magnetic bias fields.
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27
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Chen H, Asif S, Dolui K, Wang Y, Támara-Isaza J, Goli VMLDP, Whalen M, Wang X, Chen Z, Zhang H, Liu K, Jariwala D, Jungfleisch MB, Chakraborty C, May AF, McGuire MA, Nikolic BK, Xiao JQ, Ku MJH. Above-Room-Temperature Ferromagnetism in Thin van der Waals Flakes of Cobalt-Substituted Fe 5GeTe 2. ACS APPLIED MATERIALS & INTERFACES 2023; 15:3287-3296. [PMID: 36602594 DOI: 10.1021/acsami.2c18028] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Two-dimensional (2D) magnetic van der Waals materials provide a powerful platform for studying the fundamental physics of low-dimensional magnetism, engineering novel magnetic phases, and enabling thin and highly tunable spintronic devices. To realize high-quality and practical devices for such applications, there is a critical need for robust 2D magnets with ordering temperatures above room temperature that can be created via exfoliation. Here, the study of exfoliated flakes of cobalt-substituted Fe5GeTe2 (CFGT) exhibiting magnetism above room temperature is reported. Via quantum magnetic imaging with nitrogen-vacancy centers in diamond, ferromagnetism at room temperature was observed in CFGT flakes as thin as 16 nm corresponding to 16 layers. This result expands the portfolio of thin room-temperature 2D magnet flakes exfoliated from robust single crystals that reach a thickness regime relevant to practical spintronic applications. The Curie temperature Tc of CFGT ranges from 310 K in the thinnest flake studied to 328 K in the bulk. To investigate the prospect of high-temperature monolayer ferromagnetism, Monte Carlo calculations were performed, which predicted a high value of Tc of ∼270 K in CFGT monolayers. Pathways toward further enhancing monolayer Tc are discussed. These results support CFGT as a promising platform for realizing high-quality room-temperature 2D magnet devices.
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Affiliation(s)
- Hang Chen
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Shahidul Asif
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware19716, United States
| | - Kapildeb Dolui
- Lomare Technologies Ltd., 6 London Street, LondonEC3R 7LP, United Kingdom
| | - Yang Wang
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Jeyson Támara-Isaza
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
- Departamento de Física, Universidad Nacional de Colombia, Bogotá D.C.110851, Colombia
| | - V M L Durga Prasad Goli
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Matthew Whalen
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Xinhao Wang
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Zhijie Chen
- Department of Physics, Georgetown University, Washington, District of Columbia20057, United States
| | - Huiqin Zhang
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
| | - Kai Liu
- Department of Physics, Georgetown University, Washington, District of Columbia20057, United States
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
| | - M Benjamin Jungfleisch
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Chitraleema Chakraborty
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware19716, United States
| | - Andrew F May
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States
| | - Michael A McGuire
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States
| | - Branislav K Nikolic
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - John Q Xiao
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
| | - Mark J H Ku
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware19716, United States
- Department of Materials Science and Engineering, University of Delaware, Newark, Delaware19716, United States
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28
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Rovny J, Yuan Z, Fitzpatrick M, Abdalla AI, Futamura L, Fox C, Cambria MC, Kolkowitz S, de Leon NP. Nanoscale covariance magnetometry with diamond quantum sensors. Science 2022; 378:1301-1305. [PMID: 36548408 DOI: 10.1126/science.ade9858] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Nitrogen vacancy (NV) centers in diamond are atom-scale defects that can be used to sense magnetic fields with high sensitivity and spatial resolution. Typically, the magnetic field is measured by averaging sequential measurements of single NV centers, or by spatial averaging over ensembles of many NV centers, which provides mean values that contain no nonlocal information about the relationship between two points separated in space or time. Here, we propose and implement a sensing modality whereby two or more NV centers are measured simultaneously, and we extract temporal and spatial correlations in their signals that would otherwise be inaccessible. We demonstrate measurements of correlated applied noise using spin-to-charge readout of two NV centers and implement a spectral reconstruction protocol for disentangling local and nonlocal noise sources.
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Affiliation(s)
- Jared Rovny
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Zhiyang Yuan
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Mattias Fitzpatrick
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Ahmed I Abdalla
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Laura Futamura
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Carter Fox
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | | | - Shimon Kolkowitz
- Department of Physics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Nathalie P de Leon
- Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544, USA
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29
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Chen B, Chen B, Zhu X, Fan J, Yu Z, Qian P, Xu N. Sensitivity-enhanced magnetometry using nitrogen-vacancy ensembles via adaptively complete transitions overlapping. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2022; 93:125105. [PMID: 36586914 DOI: 10.1063/5.0121925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/14/2022] [Indexed: 06/17/2023]
Abstract
Nitrogen-vacancy (NV) centers in diamond are suitable sensors of high-sensitivity magnetometry, which have attracted much interest in recent years. Here, we demonstrate sensitivity-enhanced ensemble magnetometry via adaptively complete transitions overlapping with a bias magnetic field equally projecting onto all existing NV orientations. Under such conditions, the spin transitions corresponding to different NV orientations are completely overlapped, which will bring about an obviously improved photoluminescence contrast. We, furthermore, introduce particle swarm optimization into the calibration process, to generate this bias magnetic field automatically and adaptively using computer-controlled Helmholtz coils. By applying this technique, we realize an ∼1.5 times enhancement and obtain a magnetic field sensitivity of 855pT/Hz by utilizing a group of completely overlapped transitions, compared to the 1.33nT/Hz obtained utilizing a single transition in continuous-wave magnetometry. Our approach can be conveniently applied in direction-fixed magnetic sensing and to obtain the potentially maximum sensitivity of ensemble-NV magnetometry.
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Affiliation(s)
- Bao Chen
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Bing Chen
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Xinyi Zhu
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Jingwei Fan
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Zhifei Yu
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Peng Qian
- School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Nanyang Xu
- Research Center for Quantum Sensing, Zhejiang Lab, Hangzhou 311000, China
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30
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Park BC, Ha T, Sim KI, Jung TS, Kim JH, Kim Y, Lee YH, Kim TT, Kim SW. Real-space imaging and control of chiral anomaly induced current at room temperature in topological Dirac semimetal. SCIENCE ADVANCES 2022; 8:eabq2479. [PMID: 36427320 PMCID: PMC9699670 DOI: 10.1126/sciadv.abq2479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
Chiral fermions (CFs) in condensed matters, distinguished by right (+) or left (-) handedness, hold a promise for emergent quantum devices. Although a chiral anomaly induced current, Jchiral = J(+) - J(-), occurs in Weyl semimetals due to the charge imbalance of the CFs, monitoring spatial flow and temporal dynamics of Jchiral has not been demonstrated yet. Here, we report real-space imaging and control of Jchiral on the topological Dirac semimetal KZnBi at room temperature (RT) by near-field terahertz (THz) spectroscopy, establishing a relation for an electromagnetic control of Jchiral. In THz electric and external magnetic fields, we visualize a spatial flow of coherent Jchiral in macroscopic length scale and monitor its temporal dynamics in picosecond time scale, revealing its ultralong transport length around 100 micrometers. Such coherent Jchiral is further found to be controlled according to field directions, suggesting the feasibility of information science with topological Dirac semimetals at RT.
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Affiliation(s)
- Byung Cheol Park
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Taewoo Ha
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kyung Ik Sim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Taek Sun Jung
- Department of Physics, Yonsei University, Seoul 03722, Republic of Korea
| | - Jae Hoon Kim
- Department of Physics, Yonsei University, Seoul 03722, Republic of Korea
| | - Yeongkwan Kim
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Young Hee Lee
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Teun-Teun Kim
- Department of Physics, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Sung Wng Kim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
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31
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Laorenza DW, Freedman DE. Could the Quantum Internet Be Comprised of Molecular Spins with Tunable Optical Interfaces? J Am Chem Soc 2022; 144:21810-21825. [DOI: 10.1021/jacs.2c07775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Daniel W. Laorenza
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts02139, United States
| | - Danna E. Freedman
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts02139, United States
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32
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In C, Kim UJ, Choi H. Two-dimensional Dirac plasmon-polaritons in graphene, 3D topological insulator and hybrid systems. LIGHT, SCIENCE & APPLICATIONS 2022; 11:313. [PMID: 36302746 PMCID: PMC9613982 DOI: 10.1038/s41377-022-01012-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/22/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Collective oscillations of massless particles in two-dimensional (2D) Dirac materials offer an innovative route toward implementing atomically thin devices based on low-energy quasiparticle interactions. Strong confinement of near-field distribution on the 2D surface is essential to demonstrate extraordinary optoelectronic functions, providing means to shape the spectral response at the mid-infrared (IR) wavelength. Although the dynamic polarization from the linear response theory has successfully accounted for a range of experimental observations, a unified perspective was still elusive, connecting the state-of-the-art developments based on the 2D Dirac plasmon-polaritons. Here, we review recent works on graphene and three-dimensional (3D) topological insulator (TI) plasmon-polariton, where the mid-IR and terahertz (THz) radiation experiences prominent confinement into a deep-subwavelength scale in a novel optoelectronic structure. After presenting general light-matter interactions between 2D Dirac plasmon and subwavelength quasiparticle excitations, we introduce various experimental techniques to couple the plasmon-polaritons with electromagnetic radiations. Electrical and optical controls over the plasmonic excitations reveal the hybridized plasmon modes in graphene and 3D TI, demonstrating an intense near-field interaction of 2D Dirac plasmon within the highly-compressed volume. These findings can further be applied to invent optoelectronic bio-molecular sensors, atomically thin photodetectors, and laser-driven light sources.
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Affiliation(s)
- Chihun In
- Department of Physics, Freie Universität Berlin, Berlin, 14195, Germany
- Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin, 14195, Germany
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea
- Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Un Jeong Kim
- Advanced Sensor Laboratory, Samsung Advanced Institute of Technology, Suwon, Gyeonggi-do, 16419, Republic of Korea.
| | - Hyunyong Choi
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea.
- Institute of Applied Physics, Seoul National University, Seoul, 08826, Republic of Korea.
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33
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Basso L, Kehayias P, Henshaw J, Saleh Ziabari M, Byeon H, Lilly MP, Bussmann E, Campbell DM, Misra S, Mounce AM. Electric current paths in a Si:P delta-doped device imaged by nitrogen-vacancy diamond magnetic microscopy. NANOTECHNOLOGY 2022; 34:015001. [PMID: 36170794 DOI: 10.1088/1361-6528/ac95a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
The recently-developed ability to control phosphorous-doping of silicon at an atomic level using scanning tunneling microscopy, a technique known as atomic precision advanced manufacturing (APAM), has allowed us to tailor electronic devices with atomic precision, and thus has emerged as a way to explore new possibilities in Si electronics. In these applications, critical questions include where current flow is actually occurring in or near APAM structures as well as whether leakage currents are present. In general, detection and mapping of current flow in APAM structures are valuable diagnostic tools to obtain reliable devices in digital-enhanced applications. In this paper, we used nitrogen-vacancy (NV) centers in diamond for wide-field magnetic imaging (with a few-mm field of view and micron-scale resolution) of magnetic fields from surface currents flowing in an APAM test device made of a P delta-doped layer on a Si substrate, a standard APAM witness material. We integrated a diamond having a surface NV ensemble with the device (patterned in two parallel mm-sized ribbons), then mapped the magnetic field from the DC current injected in the APAM device in a home-built NV wide-field microscope. The 2D magnetic field maps were used to reconstruct the surface current densities, allowing us to obtain information on current paths, device failures such as choke points where current flow is impeded, and current leakages outside the APAM-defined P-doped regions. Analysis on the current density reconstructed map showed a projected sensitivity of ∼0.03 A m-1, corresponding to a smallest-detectable current in the 200μm wide APAM ribbon of ∼6μA. These results demonstrate the failure analysis capability of NV wide-field magnetometry for APAM materials, opening the possibility to investigate other cutting-edge microelectronic devices.
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Affiliation(s)
- Luca Basso
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
| | - Pauli Kehayias
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
| | - Jacob Henshaw
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
| | - Maziar Saleh Ziabari
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
- Center for High Technology Materials and Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico NM-87131, United States of America
| | - Heejun Byeon
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
| | - Michael P Lilly
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
| | - Ezra Bussmann
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
| | - Deanna M Campbell
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
| | - Shashank Misra
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
| | - Andrew M Mounce
- Sandia National Laboratories, Albuquerque, New Mexico NM-87185, United States of America
- Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico NM-87123, United States of America
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34
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Stern A, Scaffidi T, Reuven O, Kumar C, Birkbeck J, Ilani S. How Electron Hydrodynamics Can Eliminate the Landauer-Sharvin Resistance. PHYSICAL REVIEW LETTERS 2022; 129:157701. [PMID: 36269972 DOI: 10.1103/physrevlett.129.157701] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 09/14/2022] [Indexed: 05/07/2023]
Abstract
It has long been realized that even a perfectly clean electronic system harbors a Landauer-Sharvin resistance, inversely proportional to the number of its conduction channels. This resistance is usually associated with voltage drops on the system's contacts to an external circuit. Recent theories have shown that hydrodynamic effects can reduce this resistance, raising the question of the lower bound of resistance of hydrodynamic electrons. Here, we show that by a proper choice of device geometry, it is possible to spread the Landauer-Sharvin resistance throughout the bulk of the system, allowing its complete elimination by electron hydrodynamics. We trace the effect to the dynamics of electrons flowing in channels that terminate within the sample. For ballistic systems this termination leads to back-reflection of the electrons and creates resistance. Hydrodynamically, the scattering of these electrons off other electrons allows them to transfer to transmitted channels and avoid the resistance. Counterintuitively, we find that in contrast to the ohmic regime, for hydrodynamic electrons the resistance of a device with a given width can decrease with its length, suggesting that a long enough device may have an arbitrarily small total resistance.
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Affiliation(s)
- Ady Stern
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Thomas Scaffidi
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
- Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 1A7, Canada
| | - Oren Reuven
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Chandan Kumar
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - John Birkbeck
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shahal Ilani
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
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35
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Huang M, Zhou J, Chen D, Lu H, McLaughlin NJ, Li S, Alghamdi M, Djugba D, Shi J, Wang H, Du CR. Wide field imaging of van der Waals ferromagnet Fe3GeTe2 by spin defects in hexagonal boron nitride. Nat Commun 2022; 13:5369. [PMID: 36100604 PMCID: PMC9470674 DOI: 10.1038/s41467-022-33016-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 08/26/2022] [Indexed: 11/26/2022] Open
Abstract
Emergent color centers with accessible spins hosted by van der Waals materials have attracted substantial interest in recent years due to their significant potential for implementing transformative quantum sensing technologies. Hexagonal boron nitride (hBN) is naturally relevant in this context due to its remarkable ease of integration into devices consisting of low-dimensional materials. Taking advantage of boron vacancy spin defects in hBN, we report nanoscale quantum imaging of low-dimensional ferromagnetism sustained in Fe3GeTe2/hBN van der Waals heterostructures. Exploiting spin relaxometry methods, we have further observed spatially varying magnetic fluctuations in the exfoliated Fe3GeTe2 flake, whose magnitude reaches a peak value around the Curie temperature. Our results demonstrate the capability of spin defects in hBN of investigating local magnetic properties of layered materials in an accessible and precise way, which can be extended readily to a broad range of miniaturized van der Waals heterostructure systems. Hexagonal boron nitride (h-BN) has been used extensively to encapsulate other van der Waals materials, protecting them from environmental degradation, and allowing integration into more complex heterostructures. Here, the authors make use of boron vacancy spin defects in h-BN using them to image the magnetic properties of a Fe3GeTe2 flake.
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36
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Tsukamoto M, Ito S, Ogawa K, Ashida Y, Sasaki K, Kobayashi K. Accurate magnetic field imaging using nanodiamond quantum sensors enhanced by machine learning. Sci Rep 2022; 12:13942. [PMID: 36050487 PMCID: PMC9436989 DOI: 10.1038/s41598-022-18115-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/05/2022] [Indexed: 11/09/2022] Open
Abstract
Nanodiamonds can be excellent quantum sensors for local magnetic field measurements. We demonstrate magnetic field imaging with high accuracy of 1.8 \documentclass[12pt]{minimal}
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\begin{document}$$\upmu $$\end{document}μT combining nanodiamond ensemble (NDE) and machine learning without any physical models. We discover the dependence of the NDE signal on the field direction, suggesting the application of NDE for vector magnetometry and the improvement of the existing model. Our method enhances the NDE performance sufficiently to visualize nano-magnetism and mesoscopic current and expands the applicability of NDE in arbitrarily shaped materials, including living organisms. This accomplishment bridges machine learning to quantum sensing for accurate measurements.
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Affiliation(s)
- Moeta Tsukamoto
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Shuji Ito
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kensuke Ogawa
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yuto Ashida
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Institute for Physics of Intelligence, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kento Sasaki
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kensuke Kobayashi
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Institute for Physics of Intelligence, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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37
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Kumar C, Birkbeck J, Sulpizio JA, Perello D, Taniguchi T, Watanabe K, Reuven O, Scaffidi T, Stern A, Geim AK, Ilani S. Imaging hydrodynamic electrons flowing without Landauer-Sharvin resistance. Nature 2022; 609:276-281. [PMID: 36071191 DOI: 10.1038/s41586-022-05002-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 06/21/2022] [Indexed: 11/09/2022]
Abstract
Electrical resistance usually originates from lattice imperfections. However, even a perfect lattice has a fundamental resistance limit, given by the Landauer1 conductance caused by a finite number of propagating electron modes. This resistance, shown by Sharvin2 to appear at the contacts of electronic devices, sets the ultimate conduction limit of non-interacting electrons. Recent years have seen growing evidence of hydrodynamic electronic phenomena3-18, prompting recent theories19,20 to ask whether an electronic fluid can radically break the fundamental Landauer-Sharvin limit. Here, we use single-electron-transistor imaging of electronic flow in high-mobility graphene Corbino disk devices to answer this question. First, by imaging ballistic flows at liquid-helium temperatures, we observe a Landauer-Sharvin resistance that does not appear at the contacts but is instead distributed throughout the bulk. This underpins the phase-space origin of this resistance-as emerging from spatial gradients in the number of conduction modes. At elevated temperatures, by identifying and accounting for electron-phonon scattering, we show the details of the purely hydrodynamic flow. Strikingly, we find that electron hydrodynamics eliminates the bulk Landauer-Sharvin resistance. Finally, by imaging spiralling magneto-hydrodynamic Corbino flows, we show the key emergent length scale predicted by hydrodynamic theories-the Gurzhi length. These observations demonstrate that electronic fluids can dramatically transcend the fundamental limitations of ballistic electrons, with important implications for fundamental science and future technologies.
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Affiliation(s)
- C Kumar
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - J Birkbeck
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - J A Sulpizio
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - D Perello
- School of Physics & Astronomy, University of Manchester, Manchester, UK.,National Graphene Institute, University of Manchester, Manchester, UK
| | - T Taniguchi
- National Institute for Materials Science, Tsukuba, Japan
| | - K Watanabe
- National Institute for Materials Science, Tsukuba, Japan
| | - O Reuven
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - T Scaffidi
- Department of Physics, University of Toronto, Toronto, ON, Canada.,Department of Physics and Astronomy, University of California, Irvine, CA, USA
| | - Ady Stern
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - A K Geim
- School of Physics & Astronomy, University of Manchester, Manchester, UK.,National Graphene Institute, University of Manchester, Manchester, UK
| | - S Ilani
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel.
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38
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Jenkins A, Baumann S, Zhou H, Meynell SA, Daipeng Y, Watanabe K, Taniguchi T, Lucas A, Young AF, Bleszynski Jayich AC. Imaging the Breakdown of Ohmic Transport in Graphene. PHYSICAL REVIEW LETTERS 2022; 129:087701. [PMID: 36053708 DOI: 10.1103/physrevlett.129.087701] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
Ohm's law describes the proportionality of the current density and electric field. In solid-state conductors, Ohm's law emerges due to electron scattering processes that relax the electrical current. Here, we use nitrogen-vacancy center magnetometry to directly image the local breakdown of Ohm's law in a narrow constriction fabricated in a high mobility graphene monolayer. Ohmic flow is visible at room temperature as current concentration on the constriction edges, with flow profiles entirely determined by sample geometry. However, as the temperature is lowered below 200 K, the current concentrates near the constriction center. The change in the flow pattern is consistent with a crossover from diffusive to viscous electron transport dominated by electron-electron scattering processes that do not relax current.
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Affiliation(s)
- Alec Jenkins
- Department of Physics, University of California, Santa Barbara California 93106, USA
| | - Susanne Baumann
- Department of Physics, University of California, Santa Barbara California 93106, USA
| | - Haoxin Zhou
- Department of Physics, University of California, Santa Barbara California 93106, USA
| | - Simon A Meynell
- Department of Physics, University of California, Santa Barbara California 93106, USA
| | - Yang Daipeng
- Department of Physics, University of California, Santa Barbara California 93106, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Andrew Lucas
- Department of Physics and Center for Theory of Quantum Matter, University of Colorado, Boulder Colorado 80309 USA
| | - Andrea F Young
- Department of Physics, University of California, Santa Barbara California 93106, USA
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39
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McLaughlin NJ, Hu C, Huang M, Zhang S, Lu H, Yan GQ, Wang H, Tserkovnyak Y, Ni N, Du CR. Quantum Imaging of Magnetic Phase Transitions and Spin Fluctuations in Intrinsic Magnetic Topological Nanoflakes. NANO LETTERS 2022; 22:5810-5817. [PMID: 35816128 DOI: 10.1021/acs.nanolett.2c01390] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Topological materials featuring exotic band structures, unconventional current flow patterns, and emergent organizing principles offer attractive platforms for the development of next-generation transformative quantum electronic technologies. The family of MnBi2Te4 (Bi2Te3)n materials is naturally relevant in this context due to their nontrivial band topology, tunable magnetism, and recently discovered extraordinary quantum transport behaviors. Despite numerous pioneering studies to date, the local magnetic properties of MnBi2Te4 (Bi2Te3)n remain an open question, hindering a comprehensive understanding of their fundamental material properties. Exploiting nitrogen-vacancy (NV) centers in diamond, we report nanoscale quantum imaging of the magnetic phase transitions and spin fluctuations in exfoliated MnBi4Te7 flakes, revealing the underlying spin transport physics and magnetic domains at the nanoscale. Our results highlight the unique advantage of NV centers in exploring the magnetic properties of emergent quantum materials, opening new opportunities for investigating the interplay between topology and magnetism.
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Affiliation(s)
- Nathan J McLaughlin
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
| | - Chaowei Hu
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Mengqi Huang
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
| | - Shu Zhang
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Hanyi Lu
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
| | - Gerald Q Yan
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
| | - Hailong Wang
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093, United States
| | - Yaroslav Tserkovnyak
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Ni Ni
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Chunhui Rita Du
- Department of Physics, University of California, San Diego, La Jolla, California 92093, United States
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093, United States
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40
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Vortices produced and studied in electron fluids. Nature 2022:10.1038/d41586-022-01557-7. [PMID: 35794381 DOI: 10.1038/d41586-022-01557-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Direct observation of vortices in an electron fluid. Nature 2022; 607:74-80. [PMID: 35794267 DOI: 10.1038/s41586-022-04794-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 04/22/2022] [Indexed: 11/09/2022]
Abstract
Vortices are the hallmarks of hydrodynamic flow. Strongly interacting electrons in ultrapure conductors can display signatures of hydrodynamic behaviour, including negative non-local resistance1-4, higher-than-ballistic conduction5-7, Poiseuille flow in narrow channels8-10 and violation of the Wiedemann-Franz law11. Here we provide a visualization of whirlpools in an electron fluid. By using a nanoscale scanning superconducting quantum interference device on a tip12, we image the current distribution in a circular chamber connected through a small aperture to a current-carrying strip in the high-purity type II Weyl semimetal WTe2. In this geometry, the Gurzhi momentum diffusion length and the size of the aperture determine the vortex stability phase diagram. We find that vortices are present for only small apertures, whereas the flow is laminar (non-vortical) for larger apertures. Near the vortical-to-laminar transition, we observe the single vortex in the chamber splitting into two vortices; this behaviour is expected only in the hydrodynamic regime and is not anticipated for ballistic transport. These findings suggest a new mechanism of hydrodynamic flow in thin pure crystals such that the spatial diffusion of electron momenta is enabled by small-angle scattering at the surfaces instead of the routinely invoked electron-electron scattering, which becomes extremely weak at low temperatures. This surface-induced para-hydrodynamics, which mimics many aspects of conventional hydrodynamics including vortices, opens new possibilities for exploring and using electron fluidics in high-mobility electron systems.
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42
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Kalhor F, Opondo NF, Mahmud S, Bauer L, Yang LP, Bhave SA, Jacob Z. Optically induced static magnetic field in the ensemble of nitrogen-vacancy centers in diamond. OPTICS LETTERS 2022; 47:3347-3350. [PMID: 35776622 DOI: 10.1364/ol.460836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/11/2022] [Indexed: 06/15/2023]
Abstract
Generation of a local magnetic field at the nanoscale is desirable for many applications such as spin-qubit-based quantum memories. However, this is a challenge due to the slow decay of static magnetic fields. Here, we demonstrate a photonic spin density (PSD)-induced effective static magnetic field for an ensemble of nitrogen-vacancy (NV) centers in bulk diamond. This locally induced magnetic field is a result of coherent interaction between the optical excitation and the NV centers. We demonstrate an optically induced spin rotation on the Bloch sphere exceeding 10 degrees which has potential applications in all-optical coherent control of spin qubits.
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43
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Huxter WS, Palm ML, Davis ML, Welter P, Lambert CH, Trassin M, Degen CL. Scanning gradiometry with a single spin quantum magnetometer. Nat Commun 2022; 13:3761. [PMID: 35768430 PMCID: PMC9243102 DOI: 10.1038/s41467-022-31454-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 06/16/2022] [Indexed: 12/03/2022] Open
Abstract
Quantum sensors based on spin defects in diamond have recently enabled detailed imaging of nanoscale magnetic patterns, such as chiral spin textures, two-dimensional ferromagnets, or superconducting vortices, based on a measurement of the static magnetic stray field. Here, we demonstrate a gradiometry technique that significantly enhances the measurement sensitivity of such static fields, leading to new opportunities in the imaging of weakly magnetic systems. Our method relies on the mechanical oscillation of a single nitrogen-vacancy center at the tip of a scanning diamond probe, which up-converts the local spatial gradients into ac magnetic fields enabling the use of sensitive ac quantum protocols. We show that gradiometry provides important advantages over static field imaging: (i) an order-of-magnitude better sensitivity, (ii) a more localized and sharper image, and (iii) a strong suppression of field drifts. We demonstrate the capabilities of gradiometry by imaging the nanotesla fields appearing above topographic defects and atomic steps in an antiferromagnet, direct currents in a graphene device, and para- and diamagnetic metals.
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Affiliation(s)
- W S Huxter
- Department of Physics, ETH Zurich, Otto Stern Weg 1, 8093, Zurich, Switzerland
| | - M L Palm
- Department of Physics, ETH Zurich, Otto Stern Weg 1, 8093, Zurich, Switzerland
| | - M L Davis
- Department of Physics, ETH Zurich, Otto Stern Weg 1, 8093, Zurich, Switzerland
| | - P Welter
- Department of Physics, ETH Zurich, Otto Stern Weg 1, 8093, Zurich, Switzerland
| | - C-H Lambert
- Department of Materials, ETH Zurich, Hönggerbergring 64, 8093, Zurich, Switzerland
| | - M Trassin
- Department of Materials, ETH Zurich, Vladimir Prelog Weg 1-5/10, 8093, Zurich, Switzerland
| | - C L Degen
- Department of Physics, ETH Zurich, Otto Stern Weg 1, 8093, Zurich, Switzerland.
- Quantum Center, ETH Zurich, 8093, Zurich, Switzerland.
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44
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Gungor AC, Koepfli SM, Baumann M, Ibili H, Smajic J, Leuthold J. Modeling Hydrodynamic Charge Transport in Graphene. MATERIALS 2022; 15:ma15124141. [PMID: 35744200 PMCID: PMC9228317 DOI: 10.3390/ma15124141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/03/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022]
Abstract
Graphene has exceptional electronic properties, such as zero band gap, massless carriers, and high mobility. These exotic carrier properties enable the design and development of unique graphene devices. However, traditional semiconductor solvers based on drift-diffusion equations are not capable of modeling and simulating the charge distribution and transport in graphene, accurately, to its full extent. The effects of charge inertia, viscosity, collective charge movement, contact doping, etc., cannot be accounted for by the conventional Poisson-drift-diffusion models, due to the underlying assumptions and simplifications. Therefore, this article proposes two mathematical models to analyze and simulate graphene-based devices. The first model is based on a modified nonlinear Poisson’s equation, which solves for the Fermi level and charge distribution electrostatically on graphene, by considering gating and contact doping. The second proposed solver focuses on the transport of the carriers by solving a hydrodynamic model. Furthermore, this model is applied to a Tesla-valve structure, where the viscosity and collective motion of the carriers play an important role, giving rise to rectification. These two models allow us to model unique electronic properties of graphene that could be paramount for the design of future graphene devices.
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45
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Yan GQ, Li S, Lu H, Huang M, Xiao Y, Wernert L, Brock JA, Fullerton EE, Chen H, Wang H, Du CR. Quantum Sensing and Imaging of Spin-Orbit-Torque-Driven Spin Dynamics in the Non-Collinear Antiferromagnet Mn 3 Sn. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200327. [PMID: 35322479 DOI: 10.1002/adma.202200327] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/02/2022] [Indexed: 06/14/2023]
Abstract
Novel non-collinear antiferromagnets with spontaneous time-reversal symmetry breaking, non-trivial band topology, and unconventional transport properties have received immense research interest over the past decade due to their rich physics and enormous promise in technological applications. One of the central focuses in this emerging field is exploring the relationship between the microscopic magnetic structure and exotic material properties. Here, nanoscale imaging of both spin-orbit-torque-induced deterministic magnetic switching and chiral spin rotation in non-collinear antiferromagnet Mn3 Sn films using nitrogen-vacancy (NV) centers are reported. Direct evidence of the off-resonance dipole-dipole coupling between the spin dynamics in Mn3 Sn and proximate NV centers is also demonstrated by NV relaxometry measurements. These results demonstrate the unique capabilities of NV centers in accessing the local information of the magnetic order and dynamics in these emergent quantum materials and suggest new opportunities for investigating the interplay between topology and magnetism in a broad range of topological magnets.
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Affiliation(s)
- Gerald Q Yan
- Department of Physics, University of California, La Jolla, San Diego, CA, 92093, USA
| | - Senlei Li
- Department of Physics, University of California, La Jolla, San Diego, CA, 92093, USA
| | - Hanyi Lu
- Department of Physics, University of California, La Jolla, San Diego, CA, 92093, USA
| | - Mengqi Huang
- Department of Physics, University of California, La Jolla, San Diego, CA, 92093, USA
| | - Yuxuan Xiao
- Center for Memory and Recording Research, University of California, La Jolla, San Diego, CA, 92093-0401, USA
| | - Luke Wernert
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
| | - Jeffrey A Brock
- Center for Memory and Recording Research, University of California, La Jolla, San Diego, CA, 92093-0401, USA
| | - Eric E Fullerton
- Center for Memory and Recording Research, University of California, La Jolla, San Diego, CA, 92093-0401, USA
| | - Hua Chen
- Department of Physics, Colorado State University, Fort Collins, CO, 80523, USA
- School of Advanced Materials Discovery, Colorado State University, Fort Collins, CO, 80523, USA
| | - Hailong Wang
- Center for Memory and Recording Research, University of California, La Jolla, San Diego, CA, 92093-0401, USA
| | - Chunhui Rita Du
- Department of Physics, University of California, La Jolla, San Diego, CA, 92093, USA
- Center for Memory and Recording Research, University of California, La Jolla, San Diego, CA, 92093-0401, USA
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46
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Wang QH, Bedoya-Pinto A, Blei M, Dismukes AH, Hamo A, Jenkins S, Koperski M, Liu Y, Sun QC, Telford EJ, Kim HH, Augustin M, Vool U, Yin JX, Li LH, Falin A, Dean CR, Casanova F, Evans RFL, Chshiev M, Mishchenko A, Petrovic C, He R, Zhao L, Tsen AW, Gerardot BD, Brotons-Gisbert M, Guguchia Z, Roy X, Tongay S, Wang Z, Hasan MZ, Wrachtrup J, Yacoby A, Fert A, Parkin S, Novoselov KS, Dai P, Balicas L, Santos EJG. The Magnetic Genome of Two-Dimensional van der Waals Materials. ACS NANO 2022; 16:6960-7079. [PMID: 35442017 PMCID: PMC9134533 DOI: 10.1021/acsnano.1c09150] [Citation(s) in RCA: 70] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 02/23/2022] [Indexed: 05/23/2023]
Abstract
Magnetism in two-dimensional (2D) van der Waals (vdW) materials has recently emerged as one of the most promising areas in condensed matter research, with many exciting emerging properties and significant potential for applications ranging from topological magnonics to low-power spintronics, quantum computing, and optical communications. In the brief time after their discovery, 2D magnets have blossomed into a rich area for investigation, where fundamental concepts in magnetism are challenged by the behavior of spins that can develop at the single layer limit. However, much effort is still needed in multiple fronts before 2D magnets can be routinely used for practical implementations. In this comprehensive review, prominent authors with expertise in complementary fields of 2D magnetism (i.e., synthesis, device engineering, magneto-optics, imaging, transport, mechanics, spin excitations, and theory and simulations) have joined together to provide a genome of current knowledge and a guideline for future developments in 2D magnetic materials research.
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Affiliation(s)
- Qing Hua Wang
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Amilcar Bedoya-Pinto
- NISE
Department, Max Planck Institute of Microstructure
Physics, 06120 Halle, Germany
- Instituto
de Ciencia Molecular (ICMol), Universitat
de València, 46980 Paterna, Spain
| | - Mark Blei
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Avalon H. Dismukes
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Assaf Hamo
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Sarah Jenkins
- Twist
Group,
Faculty of Physics, University of Duisburg-Essen, Campus Duisburg, 47057 Duisburg, Germany
| | - Maciej Koperski
- Institute
for Functional Intelligent Materials, National
University of Singapore, 117544 Singapore
| | - Yu Liu
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Qi-Chao Sun
- Physikalisches
Institut, University of Stuttgart, 70569 Stuttgart, Germany
| | - Evan J. Telford
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - Hyun Ho Kim
- School
of Materials Science and Engineering, Department of Energy Engineering
Convergence, Kumoh National Institute of
Technology, Gumi 39177, Korea
| | - Mathias Augustin
- Institute
for Condensed Matter Physics and Complex Systems, School of Physics
and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
| | - Uri Vool
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
- John Harvard
Distinguished Science Fellows Program, Harvard
University, Cambridge, Massachusetts 02138, United States
| | - Jia-Xin Yin
- Laboratory
for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, New Jersey 08544, United States
| | - Lu Hua Li
- Institute
for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, Victoria 3216, Australia
| | - Alexey Falin
- Institute
for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, Victoria 3216, Australia
| | - Cory R. Dean
- Department
of Physics, Columbia University, New York, New York 10027, United States
| | - Fèlix Casanova
- CIC nanoGUNE
BRTA, 20018 Donostia - San Sebastián, Basque
Country, Spain
- IKERBASQUE,
Basque Foundation for Science, 48013 Bilbao, Basque Country, Spain
| | - Richard F. L. Evans
- Department
of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Mairbek Chshiev
- Université
Grenoble Alpes, CEA, CNRS, Spintec, 38000 Grenoble, France
- Institut
Universitaire de France, 75231 Paris, France
| | - Artem Mishchenko
- Department
of Physics and Astronomy, University of
Manchester, Manchester, M13 9PL, United Kingdom
- National
Graphene Institute, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - Cedomir Petrovic
- Condensed
Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Rui He
- Department
of Electrical and Computer Engineering, Texas Tech University, 910 Boston Avenue, Lubbock, Texas 79409, United
States
| | - Liuyan Zhao
- Department
of Physics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Adam W. Tsen
- Institute
for Quantum Computing and Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Brian D. Gerardot
- SUPA, Institute
of Photonics and Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, United Kingdom
| | - Mauro Brotons-Gisbert
- SUPA, Institute
of Photonics and Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, United Kingdom
| | - Zurab Guguchia
- Laboratory
for Muon Spin Spectroscopy, Paul Scherrer
Institute, CH-5232 Villigen PSI, Switzerland
| | - Xavier Roy
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Sefaattin Tongay
- Materials
Science and Engineering, School for Engineering of Matter, Transport
and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Ziwei Wang
- Department
of Physics and Astronomy, University of
Manchester, Manchester, M13 9PL, United Kingdom
- National
Graphene Institute, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - M. Zahid Hasan
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Princeton
Institute for Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
| | - Joerg Wrachtrup
- Physikalisches
Institut, University of Stuttgart, 70569 Stuttgart, Germany
- Max Planck
Institute for Solid State Research, 70569 Stuttgart, Germany
| | - Amir Yacoby
- Department
of Physics, Harvard University, Cambridge, Massachusetts 02138, United States
- John A.
Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Albert Fert
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Unité
Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
- Department
of Materials Physics UPV/EHU, 20018 Donostia - San Sebastián, Basque Country, Spain
| | - Stuart Parkin
- NISE
Department, Max Planck Institute of Microstructure
Physics, 06120 Halle, Germany
| | - Kostya S. Novoselov
- Institute
for Functional Intelligent Materials, National
University of Singapore, 117544 Singapore
| | - Pengcheng Dai
- Department
of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Luis Balicas
- National
High Magnetic Field Laboratory, Florida
State University, Tallahassee, Florida 32310, United States
- Department
of Physics, Florida State University, Tallahassee, Florida 32306, United States
| | - Elton J. G. Santos
- Institute
for Condensed Matter Physics and Complex Systems, School of Physics
and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
- Donostia
International Physics Center (DIPC), 20018 Donostia-San Sebastián, Basque Country, Spain
- Higgs Centre
for Theoretical Physics, The University
of Edinburgh, Edinburgh EH9 3FD, United Kingdom
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47
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Parashar M, Bathla A, Shishir D, Gokhale A, Bandyopadhyay S, Saha K. Sub-second temporal magnetic field microscopy using quantum defects in diamond. Sci Rep 2022; 12:8743. [PMID: 35610314 PMCID: PMC9130321 DOI: 10.1038/s41598-022-12609-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 05/05/2022] [Indexed: 11/09/2022] Open
Abstract
Wide field-of-view magnetic field microscopy has been realised by probing shifts in optically detected magnetic resonance (ODMR) spectrum of Nitrogen Vacancy (NV) defect centers in diamond. However, these widefield diamond NV magnetometers require few to several minutes of acquisition to get a single magnetic field image, rendering the technique temporally static in it's current form. This limitation prevents application of diamond NV magnetometers to novel imaging of dynamically varying microscale magnetic field processes. Here, we show that the magnetic field imaging frame rate can be significantly enhanced by performing lock-in detection of NV photo-luminescence (PL), simultaneously over multiple pixels of a lock-in camera. A detailed protocol for synchronization of frequency modulated PL of NV centers with fast camera frame demodulation, at few kilohertz frequencies, has been experimentally demonstrated. This experimental technique allows magnetic field imaging of sub-second varying microscale currents in planar microcoils with imaging frame rates in the range of 50-200 frames per s (fps). Our work demonstrates that widefield per-pixel lock-in detection of frequency modulated NV ODMR enables dynamic magnetic field microscopy.
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Affiliation(s)
- Madhur Parashar
- Information Processing Laboratory, Department of Electronics and Electrical Communication Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India. .,School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
| | - Anuj Bathla
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India.,Centre for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India
| | - Dasika Shishir
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India
| | - Alok Gokhale
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India
| | - Sharba Bandyopadhyay
- Information Processing Laboratory, Department of Electronics and Electrical Communication Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Kasturi Saha
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India.
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48
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Matus P, Dantas RMA, Moessner R, Surówka P. Skin effect as a probe of transport regimes in Weyl semimetals. Proc Natl Acad Sci U S A 2022; 119:e2200367119. [PMID: 35286187 PMCID: PMC8944275 DOI: 10.1073/pnas.2200367119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 02/11/2022] [Indexed: 11/20/2022] Open
Abstract
SignificanceWeyl semimetals are a class of three-dimensional materials, whose low-energy excitations mimic massless fermions. In consequence they exhibit various unusual transport properties related to the presence of chiral anomalies, a subtle quantum phenomenon that denotes the breaking of the classical chiral symmetry by quantum fluctuations. In this work we present a universal description of transport in weakly disordered Weyl semimetals with several scattering mechanisms taken into account. Our work predicts the existence of a new anomaly-induced transport regime in these materials and gives a crisp experimental signature of a chiral anomaly in optical conductivity measurements. Finally, by also capturing the hydrodynamic regime of quasiparticles, our construction bridges the gap between developments in electronic fluid mechanics and three-dimensional semimetals.
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Affiliation(s)
- Paweł Matus
- Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany
- Würzburg-Dresden Cluster of Excellence Complexity and Topology in Quantum Matter (ct.qmat), 01187 Dresden, Germany
| | - Renato M. A. Dantas
- Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany
- Würzburg-Dresden Cluster of Excellence Complexity and Topology in Quantum Matter (ct.qmat), 01187 Dresden, Germany
- Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Roderich Moessner
- Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany
- Würzburg-Dresden Cluster of Excellence Complexity and Topology in Quantum Matter (ct.qmat), 01187 Dresden, Germany
| | - Piotr Surówka
- Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany
- Würzburg-Dresden Cluster of Excellence Complexity and Topology in Quantum Matter (ct.qmat), 01187 Dresden, Germany
- Department of Theoretical Physics, Wrocław University of Science and Technology, 50-370 Wrocław, Poland
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49
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Berdyugin AI, Xin N, Gao H, Slizovskiy S, Dong Z, Bhattacharjee S, Kumaravadivel P, Xu S, Ponomarenko LA, Holwill M, Bandurin DA, Kim M, Cao Y, Greenaway MT, Novoselov KS, Grigorieva IV, Watanabe K, Taniguchi T, Fal'ko VI, Levitov LS, Kumar RK, Geim AK. Out-of-equilibrium criticalities in graphene superlattices. Science 2022; 375:430-433. [PMID: 35084955 DOI: 10.1126/science.abi8627] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
In thermodynamic equilibrium, current in metallic systems is carried by electronic states near the Fermi energy, whereas the filled bands underneath contribute little to conduction. Here, we describe a very different regime in which carrier distribution in graphene and its superlattices is shifted so far from equilibrium that the filled bands start playing an essential role, leading to a critical-current behavior. The criticalities develop upon the velocity of electron flow reaching the Fermi velocity. Key signatures of the out-of-equilibrium state are current-voltage characteristics that resemble those of superconductors, sharp peaks in differential resistance, sign reversal of the Hall effect, and a marked anomaly caused by the Schwinger-like production of hot electron-hole plasma. The observed behavior is expected to be common to all graphene-based superlattices.
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Affiliation(s)
- Alexey I Berdyugin
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Na Xin
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Haoyang Gao
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Sergey Slizovskiy
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Zhiyu Dong
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Shubhadeep Bhattacharjee
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - P Kumaravadivel
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Shuigang Xu
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - L A Ponomarenko
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,Department of Physics, University of Lancaster, Lancaster LA1 4YW, UK
| | - Matthew Holwill
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - D A Bandurin
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Minsoo Kim
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - Yang Cao
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - M T Greenaway
- Department of Physics, Loughborough University, Loughborough LE11 3TU, UK.,School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK
| | - K S Novoselov
- National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
| | - I V Grigorieva
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK
| | - K Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - T Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - V I Fal'ko
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.,Henry Royce Institute for Advanced Materials, Manchester M13 9PL, UK
| | - L S Levitov
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Roshan Krishna Kumar
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK.,Institut de Ciencies Fotoniques (ICFO), Barcelona Institute of Science and Technology, 08860 Castelldefels, Barcelona, Spain
| | - A K Geim
- School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.,National Graphene Institute, University of Manchester, Manchester M13 9PL, UK
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50
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Jindra M, Velický M, Bouša M, Abbas G, Kalbáč M, Frank O. Localized Spectroelectrochemical Identification of Basal Plane and Defect-Related Charge-Transfer Processes in Graphene. J Phys Chem Lett 2022; 13:642-648. [PMID: 35020405 DOI: 10.1021/acs.jpclett.1c03466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
It is well-known that structural defects play a decisive role in electrochemical behavior of atomically thin materials, where all the defects are directly accessible by the electrolyte. However, the vast majority of experimental techniques do not allow disentanglement of the processes at the edges/defects from those at the intact basal plane. Therefore, to address this issue, we introduce a localized spectroelectrochemical method featuring a microdroplet electrochemical cell with simultaneous Raman spectroscopy monitoring. The electrochemical and spectral responses of the basal planes of monolayer graphene samples with varying levels of disorder were compared. Two contributions, stemming from the intact and defective areas on the surface, respectively, were discovered both in the Raman G band shifts and cyclic voltammetry using the hexaammineruthenium complex. Consequently, two independent electron transfer processes of slower and faster rates coexist in one sample, but they are restricted to the defect-free and defect-rich areas, respectively.
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Affiliation(s)
- Martin Jindra
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
- Department of Physical Chemistry, University of Chemistry and Technology, 16628 Prague, Czech Republic
| | - Matěj Velický
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
- Department of Physics and Astronomy, University of Manchester, Oxford Road, M13 9PL Manchester, United Kingdom
| | - Milan Bouša
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
| | - Ghulam Abbas
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
- Department of Physical Chemistry and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030, 128 43 Prague 2, Czech Republic
| | - Martin Kalbáč
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
| | - Otakar Frank
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague, Czech Republic
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