1
|
Zheng H, Cheung LY, Sangwan N, Kononov A, Haller R, Ridderbos J, Ciaccia C, Ungerer JH, Li A, Bakkers EP, Baumgartner A, Schönenberger C. Coherent Control of a Few-Channel Hole Type Gatemon Qubit. NANO LETTERS 2024; 24:7173-7179. [PMID: 38848282 PMCID: PMC11194827 DOI: 10.1021/acs.nanolett.4c00770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 05/03/2024] [Accepted: 05/06/2024] [Indexed: 06/09/2024]
Abstract
Gatemon qubits are the electrically tunable cousins of superconducting transmon qubits. In this work, we demonstrate the full coherent control of a gatemon qubit based on hole carriers in a Ge/Si core/shell nanowire, with the longest coherence times in group IV material gatemons to date. The key to these results is a high-quality Josephson junction obtained using a straightforward and reproducible annealing technique. We demonstrate that the transport through the narrow junction is dominated by only two quantum channels, with transparencies up to unity. This novel qubit platform holds great promise for quantum information applications, not only because it incorporates technologically relevant materials, but also because it provides new opportunities, like an ultrastrong spin-orbit coupling in the few-channel regime of Josephson junctions.
Collapse
Affiliation(s)
- Han Zheng
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Luk Yi Cheung
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Nikunj Sangwan
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Artem Kononov
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Roy Haller
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Joost Ridderbos
- MESA+
Institute for Nanotechnology University of Twente, 7500 AE Enschede, The Netherlands
| | - Carlo Ciaccia
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Jann Hinnerk Ungerer
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Ang Li
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - Erik P.A.M. Bakkers
- Department
of Applied Physics, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - Andreas Baumgartner
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
- Swiss
Nanoscience Institute, University of Basel, 4056 Basel, Switzerland
| | - Christian Schönenberger
- Quantum-
and Nanoelectronics Lab, Department of Physics, University of Basel, 4056 Basel, Switzerland
- Swiss
Nanoscience Institute, University of Basel, 4056 Basel, Switzerland
| |
Collapse
|
2
|
Yang L, Yue S, Tao Y, Qiao S, Li H, Dai Z, Song B, Chen Y, Du J, Li D, Gao P. Suppressed thermal transport in silicon nanoribbons by inhomogeneous strain. Nature 2024; 629:1021-1026. [PMID: 38750362 DOI: 10.1038/s41586-024-07390-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/05/2024] [Indexed: 05/31/2024]
Abstract
Nanoscale structures can produce extreme strain that enables unprecedented material properties, such as tailored electronic bandgap1-5, elevated superconducting temperature6,7 and enhanced electrocatalytic activity8,9. While uniform strains are known to elicit limited effects on heat flow10-15, the impact of inhomogeneous strains has remained elusive owing to the coexistence of interfaces16-20 and defects21-23. Here we address this gap by introducing inhomogeneous strain through bending individual silicon nanoribbons on a custom-fabricated microdevice and measuring its effect on thermal transport while characterizing the strain-dependent vibrational spectra with sub-nanometre resolution. Our results show that a strain gradient of 0.112% per nanometre could lead to a drastic thermal conductivity reduction of 34 ± 5%, in clear contrast to the nearly constant values measured under uniform strains10,12,14,15. We further map the local lattice vibrational spectra using electron energy-loss spectroscopy, which reveals phonon peak shifts of several millielectron-volts along the strain gradient. This unique phonon spectra broadening effect intensifies phonon scattering and substantially impedes thermal transport, as evidenced by first-principles calculations. Our work uncovers a crucial piece of the long-standing puzzle of lattice dynamics under inhomogeneous strain, which is absent under uniform strain and eludes conventional understanding.
Collapse
Affiliation(s)
- Lin Yang
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China.
| | - Shengying Yue
- Laboratory for Multiscale Mechanics and Medical Science, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, People's Republic of China
| | - Yi Tao
- School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, People's Republic of China
| | - Shuo Qiao
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Hang Li
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Zhaohe Dai
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Bai Song
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China
- Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Yunfei Chen
- School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, People's Republic of China
| | - Jinlong Du
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, People's Republic of China.
| | - Deyu Li
- Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Peng Gao
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, People's Republic of China.
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, People's Republic of China.
| |
Collapse
|
3
|
Ramanandan SP, Reñé Sapera J, Morelle A, Martí-Sánchez S, Rudra A, Arbiol J, Dubrovskii VG, Fontcuberta I Morral A. Control of Ge island coalescence for the formation of nanowires on silicon. NANOSCALE HORIZONS 2024; 9:555-565. [PMID: 38353654 PMCID: PMC10962639 DOI: 10.1039/d3nh00573a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 02/05/2024] [Indexed: 03/26/2024]
Abstract
Germanium nanowires could be the building blocks of hole-spin qubit quantum computers. Selective area epitaxy enables the direct integration of Ge nanowires on a silicon chip while controlling the device design, density, and scalability. For this to become a reality, it is essential to understand and control the initial stages of the epitaxy process. In this work, we highlight the importance of surface treatment in the reactor prior to growth to achieve high crystal quality and connected Ge nanowire structures. In particular, we demonstrate that exposure to AsH3 during the high-temperature treatment enhances lateral growth of initial Ge islands and promotes faster formation of continuous Ge nanowires in trenches. The Kolmogorov-Johnson-Mehl-Avrami crystallization model supports our explanation of Ge coalescence. These results provide critical insight into the selective epitaxy of horizontal Ge nanowires on lattice-mismatched Si substrates, which can be translated to other material systems.
Collapse
Affiliation(s)
- Santhanu Panikar Ramanandan
- Laboratory of Semiconductor Materials, Institute of Materials, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland.
| | - Joel Reñé Sapera
- Laboratory of Semiconductor Materials, Institute of Materials, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland.
| | - Alban Morelle
- Solid State Laboratory, ETH Zurich, 8093 Zurich, Switzerland
| | - Sara Martí-Sánchez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Catalonia, Spain
| | - Alok Rudra
- Laboratory of Semiconductor Materials, Institute of Materials, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland.
- Institute of Physics, Faculty of Basic Sciences, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland
| | - Jordi Arbiol
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Catalonia, Spain
- ICREA, Pg. Lluís Companys 23, 08010 Barcelona, Catalonia, Spain
| | - Vladimir G Dubrovskii
- Faculty of Physics, St. Petersburg State University, Universitetskaya Embankment 13B, 199034 St. Petersburg, Russia
| | - Anna Fontcuberta I Morral
- Laboratory of Semiconductor Materials, Institute of Materials, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland.
- Institute of Physics, Faculty of Basic Sciences, Ecole Polytechnique Fédérale de Lausanne EPFL, Lausanne 1015, Switzerland
- Center for Quantum Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
4
|
Badawy G, Bakkers EPAM. Electronic Transport and Quantum Phenomena in Nanowires. Chem Rev 2024; 124:2419-2440. [PMID: 38394689 PMCID: PMC10941195 DOI: 10.1021/acs.chemrev.3c00656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 01/26/2024] [Accepted: 02/08/2024] [Indexed: 02/25/2024]
Abstract
Nanowires are natural one-dimensional channels and offer new opportunities for advanced electronic quantum transport experiments. We review recent progress on the synthesis of nanowires and methods for the fabrication of hybrid semiconductor/superconductor systems. We discuss methods to characterize their electronic properties in the context of possible future applications such as topological and spin qubits. We focus on group III-V (InAs and InSb) and group IV (Ge/Si) semiconductors, since these are the most developed, and give an outlook on other potential materials.
Collapse
Affiliation(s)
- Ghada Badawy
- Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| | - Erik P. A. M. Bakkers
- Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| |
Collapse
|
5
|
Fukata N, Jevasuwan W. Formation and characterization of Group IV semiconductor nanowires. NANOTECHNOLOGY 2024; 35:122001. [PMID: 38096568 DOI: 10.1088/1361-6528/ad15b8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 12/13/2023] [Indexed: 01/05/2024]
Abstract
To enable the application to next-generation devices of semiconductor nanowires (NWs), it is important to control their formation and tune their functionality by doping and the use of heterojunctions. In this paper, we introduce formation and the characterization methods of nanowires, focusing on our research results. We describe a top-down method of controlling the size and alignment of nanowires that shows advantages over bottom-up growth methods. The latter technique causes damage to the nanowire surfaces, requiring defect removal after the NW formation process. We show various methods of evaluating the bonding state and electrical activity of impurities in NWs. If an impurity is doped in a NW, mobility decreases due to the scattering that it causes. As a strategy for solving this problem, we describe research into core-shell nanowires, in which Si and Ge heterojunctions are formed in the diameter direction inside the NW. This structure can separate the impurity-doped region from the carrier transport region, promising as a channel for the new ultimate high-mobility transistor.
Collapse
Affiliation(s)
- Naoki Fukata
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan
| | - Wipakorn Jevasuwan
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
| |
Collapse
|
6
|
Forrer N, Nigro A, Gadea G, Zardo I. Influence of Different Carrier Gases, Temperature, and Partial Pressure on Growth Dynamics of Ge and Si Nanowires. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2879. [PMID: 37947724 PMCID: PMC10650493 DOI: 10.3390/nano13212879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/23/2023] [Accepted: 10/29/2023] [Indexed: 11/12/2023]
Abstract
The broad and fascinating properties of nanowires and their synthesis have attracted great attention as building blocks for functional devices at the nanoscale. Silicon and germanium are highly interesting materials due to their compatibility with standard CMOS technology. Their combination provides optimal templates for quantum applications, for which nanowires need to be of high quality, with carefully designed dimensions, crystal phase, and orientation. In this work, we present a detailed study on the growth kinetics of silicon (length 0.1-1 μm, diameter 10-60 nm) and germanium (length 0.06-1 μm, diameter 10-500 nm) nanowires grown by chemical vapor deposition applying the vapour-liquid-solid growth method catalysed by gold. The effects of temperature, partial pressure of the precursor gas, and different carrier gases are analysed via scanning electron microscopy. Argon as carrier gas enhances the growth rate at higher temperatures (120 nm/min for Ar and 48 nm/min H2), while hydrogen enhances it at lower temperatures (35 nm/min for H2 and 22 nm/min for Ar) due to lower heat capacity. Both materials exhibit two growth regimes as a function of the temperature. The tapering rate is about ten times lower for silicon nanowires than for germanium ones. Finally, we identify the optimal conditions for nucleation in the nanowire growth process.
Collapse
Affiliation(s)
- Nicolas Forrer
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland; (N.F.); (A.N.); (G.G.)
| | - Arianna Nigro
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland; (N.F.); (A.N.); (G.G.)
| | - Gerard Gadea
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland; (N.F.); (A.N.); (G.G.)
- Swiss Nanoscience Institute, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Ilaria Zardo
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland; (N.F.); (A.N.); (G.G.)
- Swiss Nanoscience Institute, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| |
Collapse
|
7
|
Ming M, Gao F, Wang JH, Zhang JY, Wang T, Yao Y, Hu H, Zhang JJ. Strain-induced ordered Ge(Si) hut wires on patterned Si (001) substrates. NANOSCALE 2023; 15:7311-7317. [PMID: 37013680 DOI: 10.1039/d2nr05238e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Ge/Si nanowires are predicted to be a promising platform for spin and even topological qubits. While for large-scale integration of these devices, nanowires with fully controlled positions and arrangements are a prerequisite. Here, we have reported ordered Ge hut wires by multilayer heteroepitaxy on patterned Si (001) substrates. Self-assembled GeSi hut wire arrays are orderly grown inside patterned trenches with post growth surface flatness. Such embedded GeSi wires induce tensile strain on the Si surface, which results in preferential nucleation of Ge nanostructures. Ordered Ge nano-dashes, disconnected wires and continuous wires are obtained correspondingly by tuning the growth conditions. These site-controlled Ge nanowires on a flattened surface lead to the ease of fabrication and large-scale integration of nanowire quantum devices.
Collapse
Affiliation(s)
- Ming Ming
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China
- Hefei National Laboratory, Hefei 230088, China
| | - Fei Gao
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- Qilu Institute of Technology, Jinan 250200, China
| | - Jian-Huan Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- Hefei National Laboratory, Hefei 230088, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Jie-Yin Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- Hefei National Laboratory, Hefei 230088, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Ting Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- Hefei National Laboratory, Hefei 230088, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - Yuan Yao
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Hao Hu
- Hefei National Laboratory, Hefei 230088, China
- Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China
| | - Jian-Jun Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China
- Hefei National Laboratory, Hefei 230088, China
- Songshan Lake Materials Laboratory, Dongguan 523808, China
| |
Collapse
|
8
|
Hill MO, Schmiedeke P, Huang C, Maddali S, Hu X, Hruszkewycz SO, Finley JJ, Koblmüller G, Lauhon LJ. 3D Bragg Coherent Diffraction Imaging of Extended Nanowires: Defect Formation in Highly Strained InGaAs Quantum Wells. ACS NANO 2022; 16:20281-20293. [PMID: 36378999 DOI: 10.1021/acsnano.2c06071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
InGaAs quantum wells embedded in GaAs nanowires can serve as compact near-infrared emitters for direct integration onto Si complementary metal oxide semiconductor technology. While the core-shell geometry in principle allows for a greater tuning of composition and emission, especially farther into the infrared, the practical limits of elastic strain accommodation in quantum wells on multifaceted nanowires have not been established. One barrier to progress is the difficulty of directly comparing the emission characteristics and the precise microstructure of a single nanowire. Here we report an approach to correlating quantum well morphology, strain, defects, and emission to understand the limits of elastic strain accommodation in nanowire quantum wells specific to their geometry. We realize full 3D Bragg coherent diffraction imaging (BCDI) of intact quantum wells on vertically oriented epitaxial nanowires, which enables direct correlation with single-nanowire photoluminescence. By growing In0.2Ga0.8As quantum wells of distinct thicknesses on different facets of the same nanowire, we identified the critical thickness at which defects are nucleated. A correlation with a traditional transmission electron microscopy analysis confirms that BCDI can image the extended structure of defects. Finite element simulations of electron and hole states explain the emission characteristics arising from strained and partially relaxed regions. This approach, imaging the 3D strain and microstructure of intact nanowire core-shell structures with application-relevant dimensions, can aid the development of predictive models that enable the design of new compact infrared emitters.
Collapse
Affiliation(s)
- Megan O Hill
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois60208, United States
| | - Paul Schmiedeke
- Walter Schottky Institute and Physics Department, Technical University of Munich, Garching85748, Germany
| | - Chunyi Huang
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois60208, United States
| | - Siddharth Maddali
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois60439, United States
| | - Xiaobing Hu
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois60208, United States
- The NUANCE Center, Northwestern University, Evanston, Illinois60208, United States
| | - Stephan O Hruszkewycz
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois60439, United States
| | - Jonathan J Finley
- Walter Schottky Institute and Physics Department, Technical University of Munich, Garching85748, Germany
| | - Gregor Koblmüller
- Walter Schottky Institute and Physics Department, Technical University of Munich, Garching85748, Germany
| | - Lincoln J Lauhon
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois60208, United States
| |
Collapse
|
9
|
Abstract
Transistor concepts based on semiconductor nanowires promise high performance, lower energy consumption and better integrability in various platforms in nanoscale dimensions. Concerning the intrinsic transport properties of electrons in nanowires, relatively high mobility values that approach those in bulk crystals have been obtained only in core/shell heterostructures, where electrons are spatially confined inside the core. Here, it is demonstrated that the strain in lattice-mismatched core/shell nanowires can affect the effective mass of electrons in a way that boosts their mobility to distinct levels. Specifically, electrons inside the hydrostatically tensile-strained gallium arsenide core of nanowires with a thick indium aluminium arsenide shell exhibit mobility values 30–50 % higher than in equivalent unstrained nanowires or bulk crystals, as measured at room temperature. With such an enhancement of electron mobility, strained gallium arsenide nanowires emerge as a unique means for the advancement of transistor technology. Semiconductor nanowires are promising candidates for the realization of novel transistor concepts. Here, the authors demonstrate that electron mobility in strained coaxial nanowire heterostructures can be higher than in the corresponding bulk crystals.
Collapse
|
10
|
Cullen JH, Bhalla P, Marcellina E, Hamilton AR, Culcer D. Generating a Topological Anomalous Hall Effect in a Nonmagnetic Conductor: An In-Plane Magnetic Field as a Direct Probe of the Berry Curvature. PHYSICAL REVIEW LETTERS 2021; 126:256601. [PMID: 34241516 DOI: 10.1103/physrevlett.126.256601] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 04/22/2021] [Accepted: 05/27/2021] [Indexed: 06/13/2023]
Abstract
We demonstrate that the Berry curvature monopole of nonmagnetic two-dimensional spin-3/2 holes leads to a novel Hall effect linear in an applied in-plane magnetic field B_{∥}. Remarkably, all scalar and spin-dependent disorder contributions vanish to leading order in B_{∥}, while there is no Lorentz force and hence no ordinary Hall effect. This purely intrinsic phenomenon, which we term the anomalous planar Hall effect (APHE), provides a direct transport probe of the Berry curvature accessible in all p-type semiconductors. We discuss experimental setups for its measurement.
Collapse
Affiliation(s)
- James H Cullen
- School of Physics, The University of New South Wales, Sydney 2052, Australia
- Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, The University of New South Wales, Sydney 2052, Australia
| | - Pankaj Bhalla
- Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, The University of New South Wales, Sydney 2052, Australia
- Beijing Computational Science Research Center, 100193 Beijing, China
| | - E Marcellina
- School of Physics, The University of New South Wales, Sydney 2052, Australia
- Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, The University of New South Wales, Sydney 2052, Australia
| | - A R Hamilton
- School of Physics, The University of New South Wales, Sydney 2052, Australia
- Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, The University of New South Wales, Sydney 2052, Australia
| | - Dimitrie Culcer
- School of Physics, The University of New South Wales, Sydney 2052, Australia
- Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, The University of New South Wales, Sydney 2052, Australia
| |
Collapse
|
11
|
Epitaxial Growth of Ordered In-Plane Si and Ge Nanowires on Si (001). NANOMATERIALS 2021; 11:nano11030788. [PMID: 33808713 PMCID: PMC8003543 DOI: 10.3390/nano11030788] [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: 02/27/2021] [Revised: 03/14/2021] [Accepted: 03/16/2021] [Indexed: 11/16/2022]
Abstract
Controllable growth of wafer-scale in-plane nanowires (NWs) is a prerequisite for achieving addressable and scalable NW-based quantum devices. Here, by introducing molecular beam epitaxy on patterned Si structures, we demonstrate the wafer-scale epitaxial growth of site-controlled in-plane Si, SiGe, and Ge/Si core/shell NW arrays on Si (001) substrate. The epitaxially grown Si, SiGe, and Ge/Si core/shell NW are highly homogeneous with well-defined facets. Suspended Si NWs with four {111} facets and a side width of about 25 nm are observed. Characterizations including high resolution transmission electron microscopy (HRTEM) confirm the high quality of these epitaxial NWs.
Collapse
|
12
|
Froning FNM, Camenzind LC, van der Molen OAH, Li A, Bakkers EPAM, Zumbühl DM, Braakman FR. Ultrafast hole spin qubit with gate-tunable spin-orbit switch functionality. NATURE NANOTECHNOLOGY 2021; 16:308-312. [PMID: 33432204 DOI: 10.1038/s41565-020-00828-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Quantum computers promise to execute complex tasks exponentially faster than any possible classical computer, and thus spur breakthroughs in quantum chemistry, material science and machine learning. However, quantum computers require fast and selective control of large numbers of individual qubits while maintaining coherence. Qubits based on hole spins in one-dimensional germanium/silicon nanostructures are predicted to experience an exceptionally strong yet electrically tunable spin-orbit interaction, which allows us to optimize qubit performance by switching between distinct modes of ultrafast manipulation, long coherence and individual addressability. Here we used millivolt gate voltage changes to tune the Rabi frequency of a hole spin qubit in a germanium/silicon nanowire from 31 to 219 MHz, its driven coherence time between 7 and 59 ns, and its Landé g-factor from 0.83 to 1.27. We thus demonstrated spin-orbit switch functionality, with on/off ratios of roughly seven, which could be further increased through improved gate design. Finally, we used this control to optimize our qubit further and approach the strong driving regime, with spin-flipping times as short as ~1 ns.
Collapse
Affiliation(s)
| | | | - Orson A H van der Molen
- University of Basel, Basel, Switzerland
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Ang Li
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Erik P A M Bakkers
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, the Netherlands
| | | | | |
Collapse
|
13
|
Aryal S, Pati R. Spin filtering with Mn-doped Ge-core/Si-shell nanowires. NANOSCALE ADVANCES 2020; 2:1843-1849. [PMID: 36132517 PMCID: PMC9416944 DOI: 10.1039/c9na00803a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 02/27/2020] [Indexed: 06/12/2023]
Abstract
Incorporating spin functionality into a semiconductor core-shell nanowire that offers immunity from the substrate effect is a highly desirable step for its application in next generation spintronics. Here, using first-principles density functional theory that does not make any assumptions of the electronic structure, we predict that a very small amount of Mn dopants in the core region of the wire can transform the Ge-Si core-shell semiconductor nanowire into a half-metallic ferromagnet that is stable at room temperature. The energy band structures reveal a semiconducting behavior for one spin direction while the metallic behavior for the other, indicating 100% spin polarization at the Fermi energy. No measurable shifts in energy levels in the vicinity of Fermi energy are found due to spin-orbit coupling, which suggests that the spin coherence length can be much higher in this material. To further assess the use of this material in a practical device setting, we have used a quantum transport approach to calculate the spin-filtering efficiency for a channel made out of a finite nanowire segment. Our calculations yield an efficiency more than 90%, which further confirms the excellent spin-selective properties of our newly tailored Mn-doped Ge-core/Si-shell nanowires.
Collapse
Affiliation(s)
- Sandip Aryal
- Department of Physics, Michigan Technological University Houghton MI 49931 USA
| | - Ranjit Pati
- Department of Physics, Michigan Technological University Houghton MI 49931 USA
| |
Collapse
|
14
|
Kennedy OW, Zapf M, Audinot JN, Pal S, Eswara S, Wirtz T, Ronning C, Warburton PA. Photoluminescence of ZnO/ZnMgO heterostructure nanobelts grown by MBE. NANOTECHNOLOGY 2020; 31:135604. [PMID: 31825900 DOI: 10.1088/1361-6528/ab60cb] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
ZnO nanobelts may grow with their polar axis perpendicular to growth direction. Heterostructured nanobelts therefore contain hetero-interfaces along the polar axis of ZnO where polarisation mismatch may induce electron confinement. These interfaces run along the length of the nanobelts. Such heterostructure nanobelts are grown by molecular beam epitaxy and TEM images confirm the core-shell structure. The effects of shell-growth temperature on nano-heterostructures is investigated using photoluminescence and secondary ion mass spectrometry in a focussed ion-beam microscope with Ne+ as the primary ion beam. We perform low temperature photoluminescence on ensembles of such heterostructures and single nanostructures. We show how single nanobelts have photoluminescence spectra rich in features and attribute these to band misalignment at ZnO/ZnMgO interfaces embedded within nano-heterostructures.
Collapse
Affiliation(s)
- Oscar W Kennedy
- London Centre for Nanotechnology, UCL, 17-19 Gordon Street, London, WC1H 0AH, United Kingdom
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Ridderbos J, Brauns M, de Vries FK, Shen J, Li A, Kölling S, Verheijen MA, Brinkman A, van der Wiel WG, Bakkers EPAM, Zwanenburg FA. Hard Superconducting Gap and Diffusion-Induced Superconductors in Ge-Si Nanowires. NANO LETTERS 2020; 20:122-130. [PMID: 31771328 PMCID: PMC6953474 DOI: 10.1021/acs.nanolett.9b03438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/19/2019] [Indexed: 05/28/2023]
Abstract
We show a hard superconducting gap in a Ge-Si nanowire Josephson transistor up to in-plane magnetic fields of 250 mT, an important step toward creating and detecting Majorana zero modes in this system. A hard gap requires a highly homogeneous tunneling heterointerface between the superconducting contacts and the semiconducting nanowire. This is realized by annealing devices at 180 °C during which aluminum interdiffuses and replaces the germanium in a section of the nanowire. Next to Al, we find a superconductor with lower critical temperature (TC = 0.9 K) and a higher critical field (BC = 0.9-1.2 T). We can therefore selectively switch either superconductor to the normal state by tuning the temperature and the magnetic field and observe that the additional superconductor induces a proximity supercurrent in the semiconducting part of the nanowire even when the Al is in the normal state. In another device where the diffusion of Al rendered the nanowire completely metallic, a superconductor with a much higher critical temperature (TC = 2.9 K) and critical field (BC = 3.4 T) is found. The small size of these diffusion-induced superconductors inside nanowires may be of special interest for applications requiring high magnetic fields in arbitrary direction.
Collapse
Affiliation(s)
- Joost Ridderbos
- MESA
+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Matthias Brauns
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Folkert K. de Vries
- MESA
+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Jie Shen
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Ang Li
- Department
of Applied Physics, Eindhoven University
of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands
| | - Sebastian Kölling
- Department
of Applied Physics, Eindhoven University
of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands
| | - Marcel A. Verheijen
- Department
of Applied Physics, Eindhoven University
of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands
| | - Alexander Brinkman
- MESA
+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Wilfred G. van der Wiel
- MESA
+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Erik P. A. M. Bakkers
- Department
of Applied Physics, Eindhoven University
of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands
| | - Floris A. Zwanenburg
- MESA
+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| |
Collapse
|
16
|
Sistani M, Delaforce J, Kramer RBG, Roch N, Luong MA, den Hertog MI, Robin E, Smoliner J, Yao J, Lieber CM, Naud C, Lugstein A, Buisson O. Highly Transparent Contacts to the 1D Hole Gas in Ultrascaled Ge/Si Core/Shell Nanowires. ACS NANO 2019; 13:14145-14151. [PMID: 31816231 DOI: 10.1021/acsnano.9b06809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Semiconductor-superconductor hybrid systems have outstanding potential for emerging high-performance nanoelectronics and quantum devices. However, critical to their successful application is the fabrication of high-quality and reproducible semiconductor-superconductor interfaces. Here, we realize and measure axial Al-Ge-Al nanowire heterostructures with atomically precise interfaces, enwrapped by an ultrathin epitaxial Si layer further denoted as Al-Ge/Si-Al nanowire heterostructures. The heterostructures were synthesized by a thermally induced exchange reaction of single-crystalline Ge/Si core/shell nanowires and lithographically defined Al contact pads. Applying this heterostructure formation scheme enables self-aligned quasi one-dimensional crystalline Al leads contacting ultrascaled Ge/Si segments with contact transparencies greater than 96%. Integration into back-gated field-effect devices and continuous scaling beyond lithographic limitations allows us to exploit the full potential of the highly transparent contacts to the 1D hole gas at the Ge-Si interface. This leads to the observation of ballistic transport as well as quantum confinement effects up to temperatures of 150 K. Low-temperature measurements reveal proximity-induced superconductivity in the Ge/Si core/shell nanowires. The realization of a Josephson field-effect transistor allows us to study the subgap structure caused by multiple Andreev reflections. Most importantly, the absence of a quantum dot regime indicates a hard superconducting gap originating from the highly transparent contacts to the 1D hole gas, which is potentially interesting for the study of Majorana zero modes. Moreover, underlining the importance of the proposed thermally induced Al-Ge/Si-Al heterostructure formation technique, our system could contribute to the development of key components of quantum computing such as gatemon or transmon qubits.
Collapse
Affiliation(s)
- Masiar Sistani
- Institute of Solid State Electronics, TU Wien , Gußhausstraße 25-25a , 1040 Vienna , Austria
| | - Jovian Delaforce
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| | - Roman B G Kramer
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| | - Nicolas Roch
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| | - Minh Anh Luong
- Université Grenoble Alpes, CEA, IRIG-DEPHY , F-38054 Grenoble , France
| | - Martien I den Hertog
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| | - Eric Robin
- Université Grenoble Alpes, CEA, IRIG-DEPHY , F-38054 Grenoble , France
| | - Jürgen Smoliner
- Institute of Solid State Electronics, TU Wien , Gußhausstraße 25-25a , 1040 Vienna , Austria
| | - Jun Yao
- Department of Electrical and Computer Engineering, Institute for Applied Life Sciences , University of Massachusetts , Amherst , Massachusetts 01003 , United States
| | - Charles M Lieber
- Department of Chemistry and Chemical Biology , Harvard University , Cambridge , Massachusetts 02138 , United States
- School of Engineering and Applied Science , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Cecile Naud
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| | - Alois Lugstein
- Institute of Solid State Electronics, TU Wien , Gußhausstraße 25-25a , 1040 Vienna , Austria
| | - Olivier Buisson
- Université Grenoble Alpes, CNRS, Institut NEEL UPR2940 , F-38054 Grenoble , France
| |
Collapse
|
17
|
Zhang X, Jevasuwan W, Sugimoto Y, Fukata N. Controlling Catalyst-Free Formation and Hole Gas Accumulation by Fabricating Si/Ge Core-Shell and Si/Ge/Si Core-Double Shell Nanowires. ACS NANO 2019; 13:13403-13412. [PMID: 31626528 DOI: 10.1021/acsnano.9b06821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The catalyst-free formation of silicon (Si) and germanium (Ge) core-shell and core-double shell nanowires (NWs) was studied for use as building blocks of high electron (hole) mobility transistors (HEMTs). Vertically aligned p-type Si (p-Si)/intrinsic Ge (i-Ge) core-shell NWs and p-Si/i-Ge/p-Si core-double shell NWs with uniform diameters were formed by combining nanoimprint lithography, Bosch etching, and chemical vapor deposition. The boron (B) doping process was used to prepare p-Si NWs. The hole gas accumulation could be reliably detected from the i-Ge shell region in the p-Si/i-Ge core-shell NW and p-Si/i-Ge/p-Si core-double shell NW arrays through the Fano resonance effect, showing that core-shell NW heterostructures can suppress impurity scattering and act as high-mobility transistor channels. This provides the possibility for the future creation of vertical high-speed transistors.
Collapse
Affiliation(s)
- Xiaolong Zhang
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Tsukuba , Ibaraki 3050044 , Japan
- Graduate School of Pure and Applied Sciences , University of Tsukuba , Tsukuba , Ibaraki 3058573 , Japan
| | - Wipakorn Jevasuwan
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Tsukuba , Ibaraki 3050044 , Japan
| | - Yoshimasa Sugimoto
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Tsukuba , Ibaraki 3050044 , Japan
| | - Naoki Fukata
- International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Tsukuba , Ibaraki 3050044 , Japan
- Graduate School of Pure and Applied Sciences , University of Tsukuba , Tsukuba , Ibaraki 3058573 , Japan
| |
Collapse
|
18
|
Sun J, Peng M, Zhang Y, Zhang L, Peng R, Miao C, Liu D, Han M, Feng R, Ma Y, Dai Y, He L, Shan C, Pan A, Hu W, Yang ZX. Ultrahigh Hole Mobility of Sn-Catalyzed GaSb Nanowires for High Speed Infrared Photodetectors. NANO LETTERS 2019; 19:5920-5929. [PMID: 31374165 DOI: 10.1021/acs.nanolett.9b01503] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Owing to the relatively low hole mobility, the development of GaSb nanowire (NW) electronic and photoelectronic devices has stagnated in the past decade. During a typical catalyst-assisted chemical vapor deposition (CVD) process, the adopted metallic catalyst can be incorporated into the NW body to act as a slight dopant, thus regulating the electrical properties of the NW. In this work, we demonstrate the use of Sn as a catalyst and dopant for GaSb NWs in the surfactant-assisted CVD growth process. The Sn-catalyzed zinc-blende GaSb NWs are thin, long, and straight with good crystallinity, resulting in a record peak hole mobility of 1028 cm2 V-1 s-1. This high mobility is attributed to the slight doping of Sn atoms from the catalyst tip into the NW body, which is verified by the red-shifted photoluminescence peak of Sn-catalyzed GaSb NWs (0.69 eV) compared with that of Au-catalyzed NWs (0.74 eV). Furthermore, the parallel array NWs also show a high peak hole mobility of 170 cm2 V-1 s-1, a high responsivity of 61 A W-1, and fast rise and decay times of 195.1 and 380.4 μs, respectively, under the illumination of 1550 nm infrared light. All of the results demonstrate that the as-prepared Sn-catalyzed GaSb NWs are promising for application in next-generation electronics and optoelectronics.
Collapse
Affiliation(s)
- Jiamin Sun
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
| | - Meng Peng
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , Shanghai 200083 , P. R. China
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , China
| | - Yushuang Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering , Hunan University , Changsha 410082 , P. R. China
| | - Lei Zhang
- SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System , Southeast University , Nanjing 210096 , P. R. China
| | - Rui Peng
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Chengcheng Miao
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
| | - Dong Liu
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
| | - Mingming Han
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
| | - Runfa Feng
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Yandong Ma
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Ying Dai
- School of Physics , Shandong University , Jinan 250100 , P. R. China
| | - Longbing He
- SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Collaborative Innovation Center for Micro/Nano Fabrication, Device and System , Southeast University , Nanjing 210096 , P. R. China
| | - Chongxin Shan
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, School of Physics and Engineering , Zhengzhou University , Zhengzhou 450001 , China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, College of Materials Science and Engineering , Hunan University , Changsha 410082 , P. R. China
| | - Weida Hu
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , Shanghai 200083 , P. R. China
| | - Zai-Xing Yang
- School of Microelectronics , Shandong University , Jinan 250100 , P. R. China
- Shenzhen Research Institute of Shandong University , Shenzhen 518057 , P. R. China
| |
Collapse
|
19
|
Balaghi L, Bussone G, Grifone R, Hübner R, Grenzer J, Ghorbani-Asl M, Krasheninnikov AV, Schneider H, Helm M, Dimakis E. Widely tunable GaAs bandgap via strain engineering in core/shell nanowires with large lattice mismatch. Nat Commun 2019; 10:2793. [PMID: 31243278 PMCID: PMC6595053 DOI: 10.1038/s41467-019-10654-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 05/20/2019] [Indexed: 11/09/2022] Open
Abstract
The realisation of photonic devices for different energy ranges demands materials with different bandgaps, sometimes even within the same device. The optimal solution in terms of integration, device performance and device economics would be a simple material system with widely tunable bandgap and compatible with the mainstream silicon technology. Here, we show that gallium arsenide nanowires grown epitaxially on silicon substrates exhibit a sizeable reduction of their bandgap by up to 40% when overgrown with lattice-mismatched indium gallium arsenide or indium aluminium arsenide shells. Specifically, we demonstrate that the gallium arsenide core sustains unusually large tensile strain with hydrostatic character and its magnitude can be engineered via the composition and the thickness of the shell. The resulted bandgap reduction renders gallium arsenide nanowires suitable for photonic devices across the near-infrared range, including telecom photonics at 1.3 and potentially 1.55 μm, with the additional possibility of monolithic integration in silicon-CMOS chips.
Collapse
Affiliation(s)
- Leila Balaghi
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Genziana Bussone
- PETRA III, Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - Raphael Grifone
- PETRA III, Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
| | - René Hübner
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Jörg Grenzer
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Mahdi Ghorbani-Asl
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Arkady V Krasheninnikov
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Harald Schneider
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - Manfred Helm
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Center for Advancing Electronics Dresden (cfaed), Technische Universität Dresden, 01062, Dresden, Germany
| | - Emmanouil Dimakis
- Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany.
| |
Collapse
|
20
|
Kennedy OW, White ER, Shaffer MSP, Warburton PA. Vapour-liquid-solid growth of ZnO-ZnMgO core-shell nanowires by gold-catalysed molecular beam epitaxy. NANOTECHNOLOGY 2019; 30:194001. [PMID: 30793703 DOI: 10.1088/1361-6528/ab011c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Nanowire heterostructures, combining multiple phases within a single nanowire, modify functional properties and offer a platform for novel device development. Here, ZnO/ZnMgO core-shell nanowires are grown by molecular beam epitaxy. At growth temperatures above 750 °C, Mg diffuses into ZnO making heterostructure growth impossible; at lower shell-growth temperatures (500 °C), the core-shell structure is retained. Even very thin ZnMgO shells show increased intensity photoluminescence (PL) across the ZnO band-gap and a suppression in defect-related PL intensity, relative to plain ZnO nanowires. EDX measurements on shell thickness show a correlation between shell thickness and core diameter which is explained by a simple growth model.
Collapse
Affiliation(s)
- O W Kennedy
- London Centre for Nanotechnology, UCL, 17-19 Gordon Street, London, WC1H 0AH, United Kingdom
| | | | | | | |
Collapse
|
21
|
Zhang DB, Zhao XJ, Seifert G, Tse K, Zhu J. Twist-driven separation of p-type and n-type dopants in single-crystalline nanowires. Natl Sci Rev 2019; 6:532-539. [PMID: 34691902 PMCID: PMC8291436 DOI: 10.1093/nsr/nwz014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/10/2019] [Accepted: 01/19/2019] [Indexed: 11/29/2022] Open
Abstract
The distribution of dopants significantly influences the properties of semiconductors, yet effective modulation and separation of p-type and n-type dopants in homogeneous materials remain challenging, especially for nanostructures. Employing a bond orbital model with supportive atomistic simulations, we show that axial twisting can substantially modulate the radial distribution of dopants in Si nanowires (NWs) such that dopants of smaller sizes than the host atom prefer atomic sites near the NW core, while dopants of larger sizes are prone to staying adjacent to the NW surface. We attribute such distinct behaviors to the twist-induced inhomogeneous shear strain in NW. With this, our investigation on codoping pairs further reveals that with proper choices of codoping pairs, e.g. B and Sb, n-type and p-type dopants can be well separated along the NW radial dimension. Our findings suggest that twisting may lead to realizations of p-n junction configuration and modulation doping in single-crystalline NWs.
Collapse
Affiliation(s)
- Dong-Bo Zhang
- College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, China
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Xing-Ju Zhao
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Gotthard Seifert
- Theoretische Chemie, Technische Universität Dresden, Dresden D-01062, Germany
| | - Kinfai Tse
- Department of Physics, the Chinese University of Hong Kong, Hong Kong, China
| | - Junyi Zhu
- Department of Physics, the Chinese University of Hong Kong, Hong Kong, China
| |
Collapse
|
22
|
Abstract
The field of thermoelectric research has undergone a renaissance and boom in the past two and a half decades, largely fueled by the prospect of engineering electronic and phononic properties in nanostructures, among which semiconductor nanowires (NWs) have served both as an important platform to investigate fundamental thermoelectric transport phenomena and as a promising route for high thermoelectric performance for diverse applications. In this Review, we provide a comprehensive look at various aspects of thermoelectrics of NWs. We start with a brief introduction of basic thermoelectric phenomena, followed by synthetic methods for thermoelectric NWs and a summary of their thermoelectric figures of merit (ZT). We then focus our discussion on charge and heat transport, which dictate thermoelectric power factor and thermal conductivity, respectively. For charge transport, we cover the basic principles governing the power factor and then review several strategies using NWs to enhance it, including earlier theoretical and experimental work on quantum confinement effects and semimetal-to-semiconductor transition, surface engineering and complex heterostructures to enhance the carrier mobility and power factor, and the recent emergence of topological insulator NWs. For phonon transport, we broadly categorize the work on thermal conductivity of NWs into five different effects: classic size effect, acoustic softening, surface roughness, complex NW morphology, and dimensional crossover. Finally, we discuss the integration of NWs for device applications for thermoelectric power generation and cooling. We conclude our review with some outlooks for future research.
Collapse
Affiliation(s)
- Renkun Chen
- Department of Mechanical and Aerospace Engineering , The University of California-San Diego , La Jolla , California 92093 , United States
| | - Jaeho Lee
- Department of Mechanical and Aerospace Engineering , The University of California-Irvine , Irvine , California 92697 , United States
| | - Woochul Lee
- Department of Mechanical Engineering , The University of Hawaii at Manoa , Honolulu , Hawaii 96822 , United States
| | - Deyu Li
- Department of Mechanical Engineering , Vanderbilt University , Nashville , Tennessee 37235-1592 , United States
| |
Collapse
|
23
|
de Vries F, Shen J, Skolasinski RJ, Nowak MP, Varjas D, Wang L, Wimmer M, Ridderbos J, Zwanenburg FA, Li A, Koelling S, Verheijen MA, Bakkers EPAM, Kouwenhoven LP. Spin-Orbit Interaction and Induced Superconductivity in a One-Dimensional Hole Gas. NANO LETTERS 2018; 18:6483-6488. [PMID: 30192147 PMCID: PMC6187512 DOI: 10.1021/acs.nanolett.8b02981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/23/2018] [Indexed: 06/01/2023]
Abstract
Low dimensional semiconducting structures with strong spin-orbit interaction (SOI) and induced superconductivity attracted great interest in the search for topological superconductors. Both the strong SOI and hard superconducting gap are directly related to the topological protection of the predicted Majorana bound states. Here we explore the one-dimensional hole gas in germanium silicon (Ge-Si) core-shell nanowires (NWs) as a new material candidate for creating a topological superconductor. Fitting multiple Andreev reflection measurements shows that the NW has two transport channels only, underlining its one-dimensionality. Furthermore, we find anisotropy of the Landé g-factor that, combined with band structure calculations, provides us qualitative evidence for the direct Rashba SOI and a strong orbital effect of the magnetic field. Finally, a hard superconducting gap is found in the tunneling regime and the open regime, where we use the Kondo peak as a new tool to gauge the quality of the superconducting gap.
Collapse
Affiliation(s)
- Folkert
K. de Vries
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Jie Shen
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Rafal J. Skolasinski
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Michal P. Nowak
- AGH
University of Science and Technology, Academic
Centre for Materials and Nanotechnology, al. A. Mickiewicza 30, 30-059 Krakow, Poland
| | - Daniel Varjas
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Lin Wang
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Michael Wimmer
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
| | - Joost Ridderbos
- NanoElectronics
Group, MESA and Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Floris A. Zwanenburg
- NanoElectronics
Group, MESA and Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands
| | - Ang Li
- Department
of Applied Physics, Eindhoven University
of Technology, Eindhoven 5600 MB, The Netherlands
| | - Sebastian Koelling
- Department
of Applied Physics, Eindhoven University
of Technology, Eindhoven 5600 MB, The Netherlands
| | - Marcel A. Verheijen
- Department
of Applied Physics, Eindhoven University
of Technology, Eindhoven 5600 MB, The Netherlands
- Philips
Innovation Laboratories, 5656 AE Eindhoven, The Netherlands
| | - Erik P. A. M. Bakkers
- Department
of Applied Physics, Eindhoven University
of Technology, Eindhoven 5600 MB, The Netherlands
| | - Leo P. Kouwenhoven
- QuTech
and Kavli Institute of Nanoscience, Delft
University of Technology, 2600 GA Delft, The Netherlands
- Microsoft
Station Q Delft, 2600 GA Delft, The Netherlands
| |
Collapse
|
24
|
Liu H, Marcellina E, Hamilton AR, Culcer D. Strong Spin-Orbit Contribution to the Hall Coefficient of Two-Dimensional Hole Systems. PHYSICAL REVIEW LETTERS 2018; 121:087701. [PMID: 30192606 DOI: 10.1103/physrevlett.121.087701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Indexed: 06/08/2023]
Abstract
Classical charge transport, such as longitudinal and Hall currents in weak magnetic fields, is usually not affected by quantum phenomena. Yet relativistic quantum mechanics is at the heart of the spin-orbit interaction, which has been at the forefront of efforts to realize spin-based electronics, new phases of matter, and topological quantum computing. In this work we demonstrate that quantum spin dynamics induced by the spin-orbit interaction is directly observable in classical charge transport. We determine the Hall coefficient R_{H} of two-dimensional hole systems at low magnetic fields and show that it has a sizable spin-orbit contribution, which depends on the density p, is independent of temperature, is a strong function of the top gate electric field, and can reach ∼20% of the total. We provide a general method for extracting the spin-orbit parameter from magnetotransport data, applicable even at higher temperatures where Shubnikov-de Haas oscillations and weak antilocalization are difficult to observe. Our work will enable experimentalists to measure spin-orbit parameters without requiring large magnetic fields, ultralow temperatures, or optical setups.
Collapse
Affiliation(s)
- Hong Liu
- School of Physics and Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, UNSW Node, The University of New South Wales, Sydney 2052, Australia
| | - E Marcellina
- School of Physics and Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, UNSW Node, The University of New South Wales, Sydney 2052, Australia
| | - A R Hamilton
- School of Physics and Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, UNSW Node, The University of New South Wales, Sydney 2052, Australia
| | - Dimitrie Culcer
- School of Physics and Australian Research Council Centre of Excellence in Low-Energy Electronics Technologies, UNSW Node, The University of New South Wales, Sydney 2052, Australia
| |
Collapse
|
25
|
David T, Liu K, Ronda A, Favre L, Abbarchi M, Gailhanou M, Gentile P, Buttard D, Calvo V, Amato M, Aqua JN, Berbezier I. Tailoring Strain and Morphology of Core-Shell SiGe Nanowires by Low-Temperature Ge Condensation. NANO LETTERS 2017; 17:7299-7305. [PMID: 29116815 DOI: 10.1021/acs.nanolett.7b02832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Selective oxidation of the silicon element of silicon germanium (SiGe) alloys during thermal oxidation is a very important and technologically relevant mechanism used to fabricate a variety of microelectronic devices. We develop here a simple integrative approach involving vapor-liquid-solid (VLS) growth followed by selective oxidation steps to the construction of core-shell nanowires and higher-level ordered systems with scalable configurations. We examine the selective oxidation/condensation process under nonequilibrium conditions that gives rise to spontaneous formation of core-shell structures by germanium condensation. We contrast this strategy that uses reaction-diffusion-segregation mechanisms to produce coherently strained structures with highly configurable geometry and abrupt interfaces with growth-based processes which lead to low strained systems with nonuniform composition, three-dimensional morphology, and broad core-shell interface. We specially focus on SiGe core-shell nanowires and demonstrate that they can have up to 70% Ge-rich shell and 2% homogeneous strain with core diameter as small as 14 nm. Key elements of the building process associated with this approach are identified with regard to existing theoretical models. Moreover, starting from results of ab initio calculations, we discuss the electronic structure of these novel nanostructures as well as their wide potential for advanced device applications.
Collapse
Affiliation(s)
- Thomas David
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Kailang Liu
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Antoine Ronda
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Luc Favre
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Marco Abbarchi
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Marc Gailhanou
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| | - Pascal Gentile
- Université Grenoble Alpes, CEA INAC-Pheliqs- SiNaPS , F-38000 Grenoble, France
| | - Denis Buttard
- Université Grenoble Alpes, CEA INAC-Pheliqs- SiNaPS , F-38000 Grenoble, France
| | - Vincent Calvo
- Université Grenoble Alpes, CEA INAC-Pheliqs- SiNaPS , F-38000 Grenoble, France
| | - Michele Amato
- Laboratoire de Physique des Solides and Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , 91405 Orsay, France
| | | | - Isabelle Berbezier
- Aix-Marseille Université - CNRS, IM2NP, Faculté des Sciences de Jérôme , F-13397 Marseille France
| |
Collapse
|
26
|
Jaishi M, Pati R. Catching the electron in action in real space inside a Ge-Si core-shell nanowire transistor. NANOSCALE 2017; 9:13425-13431. [PMID: 28880035 DOI: 10.1039/c7nr05589g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Catching the electron in action in real space inside a semiconductor Ge-Si core-shell nanowire field effect transistor (FET), which has been demonstrated (J. Xiang, W. Lu, Y. Hu, Y. Wu, H. Yan and C. M. Lieber, Nature, 2006, 441, 489) to outperform the state-of-the-art metal oxide semiconductor FET, is central to gaining unfathomable access into the origin of its functionality. Here, using a quantum transport approach that does not make any assumptions on electronic structure, charge, and potential profile of the device, we unravel the most probable tunneling pathway for electrons in a Ge-Si core-shell nanowire FET with orbital level spatial resolution, which demonstrates gate bias induced decoupling of electron transport between the core and the shell region. Our calculation yields excellent transistor characteristics as noticed in the experiment. Upon increasing the gate bias beyond a threshold value, we observe a rapid drop in drain current resulting in a gate bias driven negative differential resistance behavior and switching in the sign of trans-conductance. We attribute this anomalous behavior in drain current to the gate bias induced modification of the carrier transport pathway from the Ge core to the Si shell region of the nanowire channel. A new experiment involving a four probe junction is proposed to confirm our prediction on gate bias induced decoupling.
Collapse
Affiliation(s)
- Meghnath Jaishi
- Department of Physics, Michigan Technological University, Houghton, MI 49931, USA.
| | | |
Collapse
|
27
|
Kotekar-Patil D, Nguyen BM, Yoo J, Dayeh SA, Frolov SM. Quasiballistic quantum transport through Ge/Si core/shell nanowires. NANOTECHNOLOGY 2017; 28:385204. [PMID: 28703121 DOI: 10.1088/1361-6528/aa7f82] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We study signatures of ballistic quantum transport of holes through Ge/Si core/shell nanowires at low temperatures. We observe Fabry-Pérot interference patterns as well as conductance plateaus at integer multiples of 2e 2/h at zero magnetic field. Magnetic field evolution of these plateaus reveals relatively large effective Landé g-factors. Ballistic effects are observed in nanowires with silicon shell thickness of 1-3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic sub-band-resolved transport.
Collapse
Affiliation(s)
- D Kotekar-Patil
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, United States of America
| | | | | | | | | |
Collapse
|