1
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Kanda N, Nakagawa M, Murotani Y, Matsunaga R. Time-domain characterization of electric field vector in multi-terahertz pulses using polarization-modulated electro-optic sampling. OPTICS EXPRESS 2024; 32:1576-1584. [PMID: 38297706 DOI: 10.1364/oe.506405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 11/22/2023] [Indexed: 02/02/2024]
Abstract
We demonstrated characterizing the electric field waveform of multi-terahertz pulses (10 - 50 THz) as vector quantities in the time domain by applying the polarization modulated electro-optic sampling (POMEOS) method. The problem of an ultrabroadband gate pulse was solved by modifying the fitting function in POMEOS, and its validity was confirmed through numerical simulations. High accuracy and precision of approximately 1 mrad with 3 s accumulation were demonstrated. Our method can be applied not only to multi-terahertz polarization measurements for linear response but also to the evaluation of the driving field of intense pulses for nonlinear response or material control.
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2
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Murotani Y, Kanda N, Fujimoto T, Matsuda T, Goyal M, Yoshinobu J, Kobayashi Y, Oka T, Stemmer S, Matsunaga R. Anomalous Hall Transport by Optically Injected Isospin Degree of Freedom in Dirac Semimetal Thin Film. NANO LETTERS 2024; 24:222-228. [PMID: 38147363 DOI: 10.1021/acs.nanolett.3c03770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Chirality of massless fermions emerging in condensed matter is a key to understand their characteristic behavior as well as to exploit their functionality. However, the chiral nature of massless fermions in Dirac semimetals has remained elusive, due to equivalent occupation of carriers with the opposite chirality in thermal equilibrium. Here, we show that the isospin degree of freedom, which labels the chirality of massless carriers from a crystallographic point of view, can be injected by circularly polarized light. Terahertz Faraday rotation spectroscopy successfully detects the anomalous Hall conductivity by a light-induced isospin polarization in a three-dimensional Dirac semimetal, Cd3As2. Spectral analysis of the Hall conductivity reveals a long scattering time and a long decay time, which are characteristic of the isospin. The long-lived, robust, and reversible character of the isospin promises a potential application of Dirac semimetals in future information technology.
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Affiliation(s)
- Yuta Murotani
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomohiro Fujimoto
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takuya Matsuda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Manik Goyal
- Materials Department, University of California, Santa Barbara, California 93106-5050, United States
| | - Jun Yoshinobu
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yohei Kobayashi
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takashi Oka
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Susanne Stemmer
- Materials Department, University of California, Santa Barbara, California 93106-5050, United States
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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3
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Liu X, Zhang D, Deng Y, Jiang N, Zhang E, Shen C, Chang K, Wang K. Tunable Spin Textures in a Kagome Antiferromagnetic Semimetal via Symmetry Design. ACS NANO 2024; 18:1013-1021. [PMID: 38147457 DOI: 10.1021/acsnano.3c10187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Kagome antiferromagnetic semimetals such as Mn3Sn have attracted extensive attention for their potential application in antiferromagnetic spintronics. Realizing high manipulation of kagome antiferromagnetic spin states at room temperature can reveal rich emergent phenomena resulting from the quantum interactions between topology, spin, and correlation. Here, we achieved tunable spin textures of Mn3Sn through symmetry design by controlling alternate Mn3Sn and heavy-metal Pt thicknesses. The various topological spin textures were predicted with theoretical simulations, and the skyrmion-induced topological Hall effect, strong spin-dependent scattering, and vertical gradient of spin states were obtained by magnetotransport and magnetic circular dichroism (MCD) spectroscopy measurements in Mn3Sn/Pt heterostructures. Our work provides an effective strategy for the innovative design of topological antiferromagnetic spintronic devices.
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Affiliation(s)
- Xionghua Liu
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dong Zhang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongcheng Deng
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nai Jiang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Enze Zhang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chao Shen
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Chang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaiyou Wang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Science, Beijing 100049, China
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4
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Fujimoto T, Kurihara T, Murotani Y, Tamaya T, Kanda N, Kim C, Yoshinobu J, Akiyama H, Kato T, Matsunaga R. Observation of Terahertz Spin Hall Conductivity Spectrum in GaAs with Optical Spin Injection. PHYSICAL REVIEW LETTERS 2024; 132:016301. [PMID: 38242663 DOI: 10.1103/physrevlett.132.016301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 11/21/2023] [Indexed: 01/21/2024]
Abstract
We report the first observation of the spin Hall conductivity spectrum in GaAs at room temperature. Our terahertz polarimetry with a precision of several μrads resolves the Faraday rotation of terahertz pulses arising from the inverse spin Hall effect of optically injected spin-polarized electrons. The obtained spin Hall conductivity spectrum exhibits an excellent quantitative agreement with theory, demonstrating a crossover in the dominant origin from impurity scattering in the dc regime to the intrinsic Berry-curvature mechanism in the terahertz regime. Our spectroscopic technique opens a new pathway to analyze anomalous transports related to spin, valley, or orbital degrees of freedom.
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Affiliation(s)
- Tomohiro Fujimoto
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takayuki Kurihara
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yuta Murotani
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomohiro Tamaya
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Changsu Kim
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Jun Yoshinobu
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Hidefumi Akiyama
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takeo Kato
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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5
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Zhao M, Guo W, Wu X, Ma L, Song P, Li G, Zhen C, Zhao D, Hou D. Zero-field-cooling exchange bias up to room temperature in the strained kagome antiferromagnet Mn 3.1Sn 0.9. MATERIALS HORIZONS 2023; 10:4597-4608. [PMID: 37593768 DOI: 10.1039/d3mh00754e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Zero-field-cooling exchange bias (ZFC EB) has always been a research hotspot for researchers, because it can realize the movement of the magnetization hysteresis loop along the field axis without field cooling, which greatly expands the universality and convenience of the application of the exchange bias effect. Achieving ZFC EB at room temperature is an ongoing challenge. To this end, a design strategy from the sublattice level is proposed, and a wide temperature range ZFC EB up to room temperature with a vertical magnetization shift is observed in the strained kagome antiferromagnet Mn3.1Sn0.9. Magnetic analysis and first-principles calculations reveal that the ZFC EB arises from the strong exchange interaction between the non-coplanar antiferromagnetic Mn kagome sublattice occupying normal Mn sites and the collinear ferromagnetic Mn sublattice occupying Sn sites. This discovery is of great significance for the application of ZFC EB in antiferromagnetic spintronic devices.
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Affiliation(s)
- Mingyue Zhao
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Wei Guo
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Xian Wu
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Li Ma
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Ping Song
- State Key Laboratory of Metastable Materials Science & Technology and Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004, People's Republic of China.
| | - Guoke Li
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Congmian Zhen
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Dewei Zhao
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
| | - Denglu Hou
- Hebei Key Laboratory of Photophysics Research and Application, College of Physics, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.
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6
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Murotani Y, Kanda N, Fujimoto T, Matsuda T, Goyal M, Yoshinobu J, Kobayashi Y, Oka T, Stemmer S, Matsunaga R. Disentangling the Competing Mechanisms of Light-Induced Anomalous Hall Conductivity in Three-Dimensional Dirac Semimetal. PHYSICAL REVIEW LETTERS 2023; 131:096901. [PMID: 37721840 DOI: 10.1103/physrevlett.131.096901] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/30/2023] [Accepted: 08/02/2023] [Indexed: 09/20/2023]
Abstract
We experimentally elucidate the origin of the anomalous Hall conductivity in a three-dimensional Dirac semimetal, Cd_{3}As_{2}, driven by circularly polarized light. Using time-resolved terahertz Faraday rotation spectroscopy, we determine the transient Hall conductivity spectrum with special attention to its sign. Our results clearly show the dominance of direct photocurrent generation assisted by the terahertz electric field. The contribution from the Floquet-Weyl nodes is found to be minor when the driving light is in resonance with interband transitions. We develop a generally applicable classification of microscopic mechanisms of light-induced anomalous Hall conductivity.
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Affiliation(s)
- Yuta Murotani
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomohiro Fujimoto
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takuya Matsuda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Manik Goyal
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | - Jun Yoshinobu
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yohei Kobayashi
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Takashi Oka
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Susanne Stemmer
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
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7
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Gao Y, Zhang Y, Zhang K, Gan Z, Yan TM, Jiang Y. Coulomb potential determining terahertz polarization in a two-color laser field. OPTICS LETTERS 2023; 48:2575-2578. [PMID: 37186712 DOI: 10.1364/ol.486464] [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
The orientation and ellipticity of terahertz (THz) polarization generated by a two-color strong field not only casts light on underlying mechanisms of laser-matter interaction, but also plays an important role for various applications. We develop the Coulomb-corrected classical trajectory Monte Carlo (CTMC) method to well reproduce the joint measurements, that the THz polarization generated by the linearly polarized 800 nm and circularly polarized 400 nm fields is independent on two-color phase delay. The trajectory analysis shows that the Coulomb potential twists the THz polarization by deflecting the orientation of asymptotic momentum of electron trajectories. Further, the CTMC calculations predict that, the two-color mid-infrared field can effectively accelerate the electron rapidly away from the parent core to relieve the disturbance of Coulomb potential, and simultaneously create large transverse acceleration of trajectories, leading to the circularly polarized THz radiation.
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8
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Matsuda T, Higo T, Koretsune T, Kanda N, Hirai Y, Peng H, Matsuo T, Yoshikawa N, Shimano R, Nakatsuji S, Matsunaga R. Ultrafast Dynamics of Intrinsic Anomalous Hall Effect in the Topological Antiferromagnet Mn_{3}Sn. PHYSICAL REVIEW LETTERS 2023; 130:126302. [PMID: 37027855 DOI: 10.1103/physrevlett.130.126302] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/06/2023] [Indexed: 06/19/2023]
Abstract
We investigate ultrafast dynamics of the anomalous Hall effect (AHE) in the topological antiferromagnet Mn_{3}Sn with sub-100 fs time resolution. Optical pulse excitations largely elevate the electron temperature up to 700 K, and terahertz probe pulses clearly resolve ultrafast suppression of the AHE before demagnetization. The result is well reproduced by microscopic calculation of the intrinsic Berry-curvature mechanism while the extrinsic contribution is clearly excluded. Our work opens a new avenue for the study of nonequilibrium AHE to identify the microscopic origin by drastic control of the electron temperature by light.
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Affiliation(s)
- Takuya Matsuda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomoya Higo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | | | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yoshua Hirai
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hanyi Peng
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takumi Matsuo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Naotaka Yoshikawa
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Ryo Shimano
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Cryogenic Research Center, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0032, Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Department of Physics, 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
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, 21218 Maryland, USA
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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9
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Spin-flip-driven anomalous Hall effect and anisotropic magnetoresistance in a layered Ising antiferromagnet. Sci Rep 2023; 13:3391. [PMID: 36854958 PMCID: PMC9974960 DOI: 10.1038/s41598-023-30076-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 02/15/2023] [Indexed: 03/02/2023] Open
Abstract
The influence of magnetocrystalline anisotropy in antiferromagnets is evident in a spin flip or flop transition. Contrary to spin flops, a spin-flip transition has been scarcely presented due to its specific condition of relatively strong magnetocrystalline anisotropy and the role of spin-flips on anisotropic phenomena has not been investigated in detail. In this study, we present antiferromagnet-based functional properties on an itinerant Ising antiferromagnet Ca0.9Sr0.1Co2As2. In the presence of a rotating magnetic field, anomalous Hall conductivity and anisotropic magnetoresistance are demonstrated, the effects of which are maximized above the spin-flip transition. Moreover, a joint experimental and theoretical study is conducted to provide an efficient tool to identify various spin states, which can be useful in spin-processing functionalities.
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10
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Deng Y, Liu X, Chen Y, Du Z, Jiang N, Shen C, Zhang E, Zheng H, Lu HZ, Wang K. All-electrical switching of a topological non-collinear antiferromagnet at room temperature. Natl Sci Rev 2023; 10:nwac154. [PMID: 36872930 PMCID: PMC9977383 DOI: 10.1093/nsr/nwac154] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 07/31/2022] [Indexed: 11/14/2022] Open
Abstract
Non-collinear antiferromagnetic Weyl semimetals, combining the advantages of a zero stray field and ultrafast spin dynamics, as well as a large anomalous Hall effect and the chiral anomaly of Weyl fermions, have attracted extensive interest. However, the all-electrical control of such systems at room temperature, a crucial step toward practical application, has not been reported. Here, using a small writing current density of around 5 × 106 A·cm-2, we realize the all-electrical current-induced deterministic switching of the non-collinear antiferromagnet Mn3Sn, with a strong readout signal at room temperature in the Si/SiO2/Mn3Sn/AlOx structure, and without external magnetic field or injected spin current. Our simulations reveal that the switching originates from the current-induced intrinsic non-collinear spin-orbit torques in Mn3Sn itself. Our findings pave the way for the development of topological antiferromagnetic spintronics.
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Affiliation(s)
- Yongcheng Deng
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xionghua Liu
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiyuan Chen
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.,International Quantum Academy, Shenzhen 518048, China
| | - Zongzheng Du
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.,International Quantum Academy, Shenzhen 518048, China
| | - Nai Jiang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chao Shen
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Enze Zhang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Houzhi Zheng
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hai-Zhou Lu
- Institute for Quantum Science and Engineering and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.,International Quantum Academy, Shenzhen 518048, China
| | - Kaiyou Wang
- State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.,Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.,Beijing Academy of Quantum Information Sciences, Beijing 100193, China.,Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
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11
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Cheng ZJ, Belopolski I, Tien HJ, Cochran TA, Yang XP, Ma W, Yin JX, Chen D, Zhang J, Jozwiak C, Bostwick A, Rotenberg E, Cheng G, Hossain MS, Zhang Q, Litskevich M, Jiang YX, Yao N, Schroeter NBM, Strocov VN, Lian B, Felser C, Chang G, Jia S, Chang TR, Hasan MZ. Visualization of Tunable Weyl Line in A-A Stacking Kagome Magnets. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2205927. [PMID: 36385535 DOI: 10.1002/adma.202205927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Kagome magnets provide a fascinating platform for a plethora of topological quantum phenomena, in which the delicate interplay between frustrated crystal structure, magnetization, and spin-orbit coupling (SOC) can engender highly tunable topological states. Here, utilizing angle-resolved photoemission spectroscopy, the Weyl lines are directly visualized with strong out-of-plane dispersion in the A-A stacked kagome magnet GdMn6 Sn6 . Remarkably, the Weyl lines exhibit a strong magnetization-direction-tunable SOC gap and binding energy tunability after substituting Gd with Tb and Li, respectively. These results not only illustrate the magnetization direction and valence counting as efficient tuning knobs for realizing and controlling distinct 3D topological phases, but also demonstrate AMn6 Sn6 (A = rare earth, or Li, Mg, or Ca) as a versatile material family for exploring diverse emergent topological quantum responses.
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Affiliation(s)
- Zi-Jia Cheng
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Ilya Belopolski
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Hung-Ju Tien
- Department of Physics, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Tyler A Cochran
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Xian P Yang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Wenlong Ma
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Jia-Xin Yin
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Dong Chen
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - Junyi Zhang
- Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Chris Jozwiak
- Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Aaron Bostwick
- Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Eli Rotenberg
- Advanced Light Source, E. O. Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Guangming Cheng
- Princeton Institute for Science and Technology of Materials, Princeton University, Princeton, NJ, 08544, USA
| | - Md Shafayat Hossain
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Qi Zhang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Maksim Litskevich
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Yu-Xiao Jiang
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Nan Yao
- Princeton Institute for Science and Technology of Materials, Princeton University, Princeton, NJ, 08544, USA
| | | | - Vladimir N Strocov
- Swiss Light Source, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Biao Lian
- Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - Claudia Felser
- Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - Guoqing Chang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Shuang Jia
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Tay-Rong Chang
- Department of Physics, National Cheng Kung University, Tainan, 70101, Taiwan
- Center for Quantum Frontiers of Research and Technology (QFort), Tainan, 701, Taiwan
- Physics Division, National Center for Theoretical Sciences, Taipei, 10617, Taiwan
| | - M Zahid Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA
- Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
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12
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Zhang K, Hu Z, Zhang L, Chen Y, Wang D, Jiang M, D'Olimpio G, Han L, Yao C, Chen Z, Xing H, Kuo CN, Lue CS, Vobornik I, Wang SW, Politano A, Hu W, Wang L, Chen X, Lu W. Ultrasensitive Self-Driven Terahertz Photodetectors Based on Low-Energy Type-II Dirac Fermions and Related Van der Waals Heterojunctions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2205329. [PMID: 36344449 DOI: 10.1002/smll.202205329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/08/2022] [Indexed: 06/16/2023]
Abstract
The exotic electronic properties of topological semimetals (TSs) have opened new pathways for innovative photonic and optoelectronic devices, especially in the highly pursuit terahertz (THz) band. However, in most cases Dirac fermions lay far above or below the Fermi level, thus hindering their successful exploitation for the low-energy photonics. Here, low-energy type-II Dirac fermions in kitkaite (NiTeSe) for ultrasensitive THz detection through metal-topological semimetal-metal heterostructures are exploited. Furthermore, a heterostructure combining two Dirac materials, namely, graphene and NiTeSe, is implemented for a novel photodetector exhibiting a responsivity as high as 1.22 A W-1 , with a response time of 0.6 µs, a noise-equivalent power of 18 pW Hz-0.5 , with outstanding stability in the ambient conditions. This work brings to fruition of Dirac fermiology in THz technology, enabling self-powered, low-power, room-temperature, and ultrafast THz detection.
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Affiliation(s)
- Kaixuan Zhang
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Zhen Hu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Libo Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No. 1, Sub-Lane Xiangshan, Xihu District, Hangzhou, 310024, China
| | - Yulu Chen
- The 50th Research Institute of China Electronics Technology Group Corporation, Shanghai, 200331, China
| | - Dong Wang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Mengjie Jiang
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Gianluca D'Olimpio
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, L'Aquila, AQ, 67100, Italy
| | - Li Han
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No. 1, Sub-Lane Xiangshan, Xihu District, Hangzhou, 310024, China
| | - Chenyu Yao
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Zhiqingzi Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Huaizhong Xing
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Chia-Nung Kuo
- Department of Physics, Cheng Kung University, 1 Ta-Hsueh Road, Taiwan, 70101, China
| | - Chin Shan Lue
- Department of Physics, Cheng Kung University, 1 Ta-Hsueh Road, Taiwan, 70101, China
| | - Ivana Vobornik
- CNR-IOM, Area Science Park, Strada Statale 14 km 163.5, Trieste, I-34149, Italy
| | - Shao-Wei Wang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Antonio Politano
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, L'Aquila, AQ, 67100, Italy
- Department of Physics, Cheng Kung University, 1 Ta-Hsueh Road, Taiwan, 70101, China
| | - Weida Hu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Lin Wang
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Xiaoshuang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
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13
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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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14
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Li P, Liu S, Chen X, Geng C, Wu X. Spintronic terahertz emission with manipulated polarization (STEMP). FRONTIERS OF OPTOELECTRONICS 2022; 15:12. [PMID: 36637604 PMCID: PMC9756272 DOI: 10.1007/s12200-022-00011-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 01/11/2022] [Indexed: 06/17/2023]
Abstract
Highly efficient generation and arbitrary manipulation of spin-polarized terahertz (THz) radiation will enable chiral lightwave driven quantum nonequilibrium state regulation, induce new electronic structures, consequently provide a powerful experimental tool for investigation of nonlinear THz optics and extreme THz science and applications. THz circular dichromic spectroscopy, ultrafast electron bunch manipulation, as well as THz imaging, sensing, and telecommunication, also need chiral THz waves. Here we review optical generation of circularly-polarized THz radiation but focus on recently emerged polarization tunable spintronic THz emission techniques, which possess many advantages of ultra-broadband, high efficiency, low cost, easy for integration and so on. We believe that chiral THz sources based on the combination of electron spin, ultrafast optical techniques and material structure engineering will accelerate the development of THz science and applications.
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Affiliation(s)
- Peiyan Li
- School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China
| | - Shaojie Liu
- School of Cyber Science and Technology, Beihang University, Beijing, 100191, China
| | - Xinhou Chen
- School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China
| | - Chunyan Geng
- School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China
| | - Xiaojun Wu
- School of Electronic and Information Engineering, Beihang University, Beijing, 100191, China.
- School of Cyber Science and Technology, Beihang University, Beijing, 100191, China.
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.
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15
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Wang L, Han L, Guo W, Zhang L, Yao C, Chen Z, Chen Y, Guo C, Zhang K, Kuo CN, Lue CS, Politano A, Xing H, Jiang M, Yu X, Chen X, Lu W. Hybrid Dirac semimetal-based photodetector with efficient low-energy photon harvesting. LIGHT, SCIENCE & APPLICATIONS 2022; 11:53. [PMID: 35273145 PMCID: PMC8913679 DOI: 10.1038/s41377-022-00741-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/26/2022] [Accepted: 02/14/2022] [Indexed: 05/06/2023]
Abstract
Despite the considerable effort, fast and highly sensitive photodetection is not widely available at the low-photon-energy range (~meV) of the electromagnetic spectrum, owing to the challenging light funneling into small active areas with efficient conversion into an electrical signal. Here, we provide an alternative strategy by efficiently integrating and manipulating at the nanoscale the optoelectronic properties of topological Dirac semimetal PtSe2 and its van der Waals heterostructures. Explicitly, we realize strong plasmonic antenna coupling to semimetal states near the skin-depth regime (λ/104), featuring colossal photoresponse by in-plane symmetry breaking. The observed spontaneous and polarization-sensitive photocurrent are correlated to strong coupling with the nonequilibrium states in PtSe2 Dirac semimetal, yielding efficient light absorption in the photon range below 1.24 meV with responsivity exceeding ∼0.2 A/W and noise-equivalent power (NEP) less than ~38 pW/Hz0.5, as well as superb ambient stability. Present results pave the way to efficient engineering of a topological semimetal for high-speed and low-energy photon harvesting in areas such as biomedical imaging, remote sensing or security applications.
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Affiliation(s)
- Lin Wang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China.
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China.
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No. 1, Sub-Lane Xiangshan, Xihu District, Hangzhou, 310024, China.
| | - Li Han
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Wanlong Guo
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Libo Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Chenyu Yao
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Zhiqingzi Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
| | - Yulu Chen
- The 50th Research Institute of China Electronics Technology Group, Shanghai, 200331, China
| | - Cheng Guo
- Research Center for Intelligent Network, Zhejiang Lab, Hangzhou, 311121, China
| | - Kaixuan Zhang
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Chia-Nung Kuo
- Department of Physics, Cheng Kung University, 1 Ta-Hsueh Road, 70101, Tainan, Taiwan, China
| | - Chin Shan Lue
- Department of Physics, Cheng Kung University, 1 Ta-Hsueh Road, 70101, Tainan, Taiwan, China
| | - Antonio Politano
- INSTM and Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, 67100, L'Aquila (AQ), Italy.
- CNR-IMM Istituto per la Microelettronica e Microsistemi, VIII strada 5, I-95121, Catania, Italy.
| | - Huaizhong Xing
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Mengjie Jiang
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Xianbin Yu
- Research Center for Intelligent Network, Zhejiang Lab, Hangzhou, 311121, China
| | - Xiaoshuang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, No. 1, Sub-Lane Xiangshan, Xihu District, Hangzhou, 310024, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-tian Road, Shanghai, 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
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16
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Seifert TS, Martens U, Radu F, Ribow M, Berritta M, Nádvorník L, Starke R, Jungwirth T, Wolf M, Radu I, Münzenberg M, Oppeneer PM, Woltersdorf G, Kampfrath T. Frequency-Independent Terahertz Anomalous Hall Effect in DyCo 5 , Co 32 Fe 68 , and Gd 27 Fe 73 Thin Films from DC to 40 THz. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2007398. [PMID: 33656190 DOI: 10.1002/adma.202007398] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/21/2020] [Indexed: 06/12/2023]
Abstract
The anomalous Hall effect (AHE) is a fundamental spintronic charge-to-charge-current conversion phenomenon and closely related to spin-to-charge-current conversion by the spin Hall effect. Future high-speed spintronic devices will crucially rely on such conversion phenomena at terahertz (THz) frequencies. Here, it is revealed that the AHE remains operative from DC up to 40 THz with a flat frequency response in thin films of three technologically relevant magnetic materials: DyCo5 , Co32 Fe68 , and Gd27 Fe73 . The frequency-dependent conductivity-tensor elements σxx and σyx are measured, and good agreement with DC measurements is found. The experimental findings are fully consistent with ab initio calculations of σyx for CoFe and highlight the role of the large Drude scattering rate (≈100 THz) of metal thin films, which smears out any sharp spectral features of the THz AHE. Finally, it is found that the intrinsic contribution to the THz AHE dominates over the extrinsic mechanisms for the Co32 Fe68 sample. The results imply that the AHE and related effects such as the spin Hall effect are highly promising ingredients of future THz spintronic devices reliably operating from DC to 40 THz and beyond.
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Affiliation(s)
- Tom S Seifert
- Department of Physics, Freie Universität Berlin, Berlin, 14195, Germany
- Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin, 14195, Germany
| | - Ulrike Martens
- Institute of Physics, University of Greifswald, Greifswald, 17489, Germany
| | - Florin Radu
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Str. 15, Berlin, 12489, Germany
| | - Mirkow Ribow
- Institute of Physics, Martin-Luther Universität Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Marco Berritta
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, Uppsala, SE-75120, Sweden
| | - Lukáš Nádvorník
- Faculty of Mathematics and Physics, Charles University, Ke Kalovu 2027/3, Prague, 12116, Czech Republic
| | | | - Tomas Jungwirth
- Institute of Physics, Czech Academy of Sciences, Cukrovarnicka 10, Praha, 6, 162 00, Czech Republic
- School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Martin Wolf
- Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin, 14195, Germany
| | - Ilie Radu
- Department of Physics, Freie Universität Berlin, Berlin, 14195, Germany
- Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Str. 2A, Berlin, 12489, Germany
| | - Markus Münzenberg
- Institute of Physics, University of Greifswald, Greifswald, 17489, Germany
| | - Peter M Oppeneer
- Institute of Physics, Martin-Luther Universität Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Georg Woltersdorf
- Institute of Physics, Martin-Luther Universität Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Tobias Kampfrath
- Department of Physics, Freie Universität Berlin, Berlin, 14195, Germany
- Department of Physical Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin, 14195, Germany
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17
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Xu H, Fei F, Chen Z, Bo X, Sun Z, Wan X, Han L, Wang L, Zhang K, Zhang J, Chen G, Liu C, Guo W, Yang L, Wei D, Song F, Chen X, Lu W. Colossal Terahertz Photoresponse at Room Temperature: A Signature of Type-II Dirac Fermiology. ACS NANO 2021; 15:5138-5146. [PMID: 33620212 DOI: 10.1021/acsnano.0c10304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The discovery of Dirac semimetal has stimulated bourgeoning interests for exploring exotic quantum-transport phenomena, holding great promise for manipulating the performance of photoelectric devices that are related to nontrivial band topology. Nevertheless, it still remains elusive on both the device implementation and immediate results, with some enhanced or technically applicable electronic properties signified by the Dirac fermiology. By means of Pt doping, a type-II Dirac semimetal Ir1-xPtxTe2 with protected crystal structure and tunable Fermi level has been achieved in this work. It has been envisioned that the metal-semimetal-metal device exhibits an order of magnitude performance improvement at terahertz frequency when the Fermi level is aligned with the Dirac node (i.e., x ∼ 0.3) and a room-temperature photoresponsivity of 0.52 A·W-1 at 0.12 THz and 0.45 A·W-1 at 0.3 THz, which benefited from the excitation of type-II Dirac fermions. Furthermore, van der Waals integration with Dirac semimetals exhibits superb performance with noise equivalent power less than 24 pW·Hz-0.5, rivaling the state-of-the-art detectors. Our work provides a route to explore the nontrivial topology of Dirac semimetal for addressing targeted applications in imaging and biomedical sensing across a terahertz gap.
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Affiliation(s)
- Huang Xu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yu-quan Road, Beijing 100049, China
| | - Fucong Fei
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Zhiqingzi Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yu-quan Road, Beijing 100049, China
| | - Xiangyan Bo
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Zhe Sun
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
| | - Xiangang Wan
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Li Han
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai 201620, China
| | - Lin Wang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yu-quan Road, Beijing 100049, China
| | - Kaixuan Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai 201620, China
| | - Jiazhen Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yu-quan Road, Beijing 100049, China
| | - Gang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
| | - Changlong Liu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Wanlong Guo
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Luhan Yang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Dacheng Wei
- State Key Laboratory of Molecular Engineering Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Fengqi Song
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Xiaoshuang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
- College of Physics and Optoelectronic Engineering, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu-Tian Road, Shanghai 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
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18
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High-frequency rectifiers based on type-II Dirac fermions. Nat Commun 2021; 12:1584. [PMID: 33707448 PMCID: PMC7952558 DOI: 10.1038/s41467-021-21906-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/18/2021] [Indexed: 11/21/2022] Open
Abstract
The advent of topological semimetals enables the exploitation of symmetry-protected topological phenomena and quantized transport. Here, we present homogeneous rectifiers, converting high-frequency electromagnetic energy into direct current, based on low-energy Dirac fermions of topological semimetal-NiTe2, with state-of-the-art efficiency already in the first implementation. Explicitly, these devices display room-temperature photosensitivity as high as 251 mA W−1 at 0.3 THz in an unbiased mode, with a photocurrent anisotropy ratio of 22, originating from the interplay between the spin-polarized surface and bulk states. Device performances in terms of broadband operation, high dynamic range, as well as their high sensitivity, validate the immense potential and unique advantages associated to the control of nonequilibrium gapless topological states via built-in electric field, electromagnetic polarization and symmetry breaking in topological semimetals. These findings pave the way for the exploitation of topological phase of matter for high-frequency operations in polarization-sensitive sensing, communications and imaging. High-frequency rectifiers at terahertz regime are pivotal components in modern communication, whereas the drawbacks in semiconductor junctions-based devices inhibit their usages. Here, the authors report electromagnetic rectification with high signal-to-noise ratio driven by chiral Bloch-electrons in type-II Dirac semimetal NiTe2-based device allowing for efficient THz detection.
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19
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Chen T, Tomita T, Minami S, Fu M, Koretsune T, Kitatani M, Muhammad I, Nishio-Hamane D, Ishii R, Ishii F, Arita R, Nakatsuji S. Anomalous transport due to Weyl fermions in the chiral antiferromagnets Mn 3X, X = Sn, Ge. Nat Commun 2021; 12:572. [PMID: 33495448 PMCID: PMC7835387 DOI: 10.1038/s41467-020-20838-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/22/2020] [Indexed: 11/28/2022] Open
Abstract
The recent discoveries of strikingly large zero-field Hall and Nernst effects in antiferromagnets Mn3X (X = Sn, Ge) have brought the study of magnetic topological states to the forefront of condensed matter research and technological innovation. These effects are considered fingerprints of Weyl nodes residing near the Fermi energy, promoting Mn3X (X = Sn, Ge) as a fascinating platform to explore the elusive magnetic Weyl fermions. In this review, we provide recent updates on the insights drawn from experimental and theoretical studies of Mn3X (X = Sn, Ge) by combining previous reports with our new, comprehensive set of transport measurements of high-quality Mn3Sn and Mn3Ge single crystals. In particular, we report magnetotransport signatures specific to chiral anomalies in Mn3Ge and planar Hall effect in Mn3Sn, which have not yet been found in earlier studies. The results summarized here indicate the essential role of magnetic Weyl fermions in producing the large transverse responses in the absence of magnetization. The large anomalous Hall (AHE) and anomalous Nernst effects (ANE) in antiferromagnets Mn3Sn/Mn3Ge are considered fingerprints of Weyl nodes residing near the Fermi energy. Here, the authors review the results from previous studies combining with new transport measurements on Mn3Sn/Mn3Ge single crystals, suggesting the essential role of magnetic Weyl fermions in explaining the AHE and ANE.
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Affiliation(s)
- Taishi Chen
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan
| | - Takahiro Tomita
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan.,CREST, Japan Science and Technology Agency (JST), Honcho Kawaguchi, Japan
| | - Susumu Minami
- Department of Physics, University of Tokyo, Tokyo, Japan.,RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan.,Nanomaterials Research Institute, Kanazawa University, Kanazawa, Japan
| | - Mingxuan Fu
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan
| | | | - Motoharu Kitatani
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan
| | - Ikhlas Muhammad
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan
| | | | - Rieko Ishii
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan
| | - Fumiyuki Ishii
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan.,Nanomaterials Research Institute, Kanazawa University, Kanazawa, Japan
| | - Ryotaro Arita
- CREST, Japan Science and Technology Agency (JST), Honcho Kawaguchi, Japan.,RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama, Japan.,Department of Applied Physics, University of Tokyo, Tokyo, Japan
| | - Satoru Nakatsuji
- Department of Physics, University of Tokyo, Tokyo, Japan. .,Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, Japan. .,CREST, Japan Science and Technology Agency (JST), Honcho Kawaguchi, Japan. .,Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, USA. .,Trans-scale Quantum Science Institute, University of Tokyo, Tokyo, Japan.
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20
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Guo C, Hu Y, Chen G, Wei D, Zhang L, Chen Z, Guo W, Xu H, Kuo CN, Lue CS, Bo X, Wan X, Wang L, Politano A, Chen X, Lu W. Anisotropic ultrasensitive PdTe 2-based phototransistor for room-temperature long-wavelength detection. SCIENCE ADVANCES 2020; 6:6/36/eabb6500. [PMID: 32917593 PMCID: PMC7467699 DOI: 10.1126/sciadv.abb6500] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/16/2020] [Indexed: 05/19/2023]
Abstract
Emergent topological Dirac semimetals afford fresh pathways for optoelectronics, although device implementation has been elusive to date. Specifically, palladium ditelluride (PdTe2) combines the capabilities provided by its peculiar band structure, with topologically protected electronic states, with advantages related to the occurrence of high-mobility charge carriers and ambient stability. Here, we demonstrate large photogalvanic effects with high anisotropy at terahertz frequency in PdTe2-based devices. A responsivity of 10 A/W and a noise-equivalent power lower than 2 pW/Hz0.5 are achieved at room temperature, validating the suitability of PdTe2-based devices for applications in photosensing, polarization-sensitive detection, and large-area fast imaging. Our findings open opportunities for exploring uncooled and sensitive photoelectronic devices based on topological semimetals, especially in the highly pursuit terahertz band.
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Affiliation(s)
- Cheng Guo
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Yibin Hu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
| | - Gang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Dacheng Wei
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Libo Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- Department of Optoelectronic Science and Engineering, Donghua University, Shanghai 201620, China
| | - Zhiqingzi Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Wanlong Guo
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Huang Xu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Chia-Nung Kuo
- Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan
| | - Chin Shan Lue
- Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan
| | - Xiangyan Bo
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Xiangang Wan
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China
| | - Lin Wang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Antonio Politano
- Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, 67100 L'Aquila (AQ), Italy.
- CNR-IMM Istituto per la Microelettronica e Microsistemi, VIII strada 5, I-95121 Catania, Italy
| | - Xiaoshuang Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
- Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
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21
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Khadka D, Thapaliya TR, Hurtado Parra S, Han X, Wen J, Need RF, Khanal P, Wang W, Zang J, Kikkawa JM, Wu L, Huang SX. Kondo physics in antiferromagnetic Weyl semimetal Mn 3+x Sn 1-x films. SCIENCE ADVANCES 2020; 6:eabc1977. [PMID: 32923648 PMCID: PMC7455184 DOI: 10.1126/sciadv.abc1977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Topology and strong electron correlations are crucial ingredients in emerging quantum materials, yet their intersection in experimental systems has been relatively limited to date. Strongly correlated Weyl semimetals, particularly when magnetism is incorporated, offer a unique and fertile platform to explore emergent phenomena in novel topological matter and topological spintronics. The antiferromagnetic Weyl semimetal Mn3Sn exhibits many exotic physical properties such as a large spontaneous Hall effect and has recently attracted intense interest. In this work, we report synthesis of epitaxial Mn3+x Sn1-x films with greatly extended compositional range in comparison with that of bulk samples. As Sn atoms are replaced by magnetic Mn atoms, the Kondo effect, which is a celebrated example of strong correlations, emerges, develops coherence, and induces a hybridization energy gap. The magnetic doping and gap opening lead to rich extraordinary properties, as exemplified by the prominent DC Hall effects and resonance-enhanced terahertz Faraday rotation.
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Affiliation(s)
- Durga Khadka
- Department of Physics, University of Miami, Coral Gables, FL 33146, USA
| | - T. R. Thapaliya
- Department of Physics, University of Miami, Coral Gables, FL 33146, USA
| | - Sebastian Hurtado Parra
- Department of Physics and Astronomy, The University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xingyue Han
- Department of Physics and Astronomy, The University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jiajia Wen
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Ryan F. Need
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20878, USA
| | - Pravin Khanal
- Department of Physics, University of Arizona, Tucson, AZ 85721, USA
| | - Weigang Wang
- Department of Physics, University of Arizona, Tucson, AZ 85721, USA
| | - Jiadong Zang
- Department of Physics and Astronomy, University of New Hampshire, Durham, NH 03824, USA
- Materials Science Program, University of New Hampshire, Durham, NH 03824, USA
| | - James M. Kikkawa
- Department of Physics and Astronomy, The University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Liang Wu
- Department of Physics and Astronomy, The University of Pennsylvania, Philadelphia, PA 19104, USA
| | - S. X. Huang
- Department of Physics, University of Miami, Coral Gables, FL 33146, USA
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