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Li Y, Du X, Wang J, Xu R, Zhao W, Zhai K, Liu J, Chen H, Yang Y, Plumb NC, Ju S, Shi M, Liu Z, Guo JG, Chen X, Chen Y, Yang L. Quantum-Confined Tunable Ferromagnetism on the Surface of a Van der Waals Antiferromagnet NaCrTe 2. NANO LETTERS 2024; 24:9832-9838. [PMID: 39101565 DOI: 10.1021/acs.nanolett.4c01542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
The surface of three-dimensional materials provides an ideal and versatile platform to explore quantum-confined physics. Here, we systematically investigate the electronic structure of Na-intercalated CrTe2, a van der Waals antiferromagnet, using angle-resolved photoemission spectroscopy and ab initio calculations. The measured band structure deviates from the calculation of bulk NaCrTe2 but agrees with that of ferromagnetic monolayer CrTe2. Consistently, we observe unexpected exchange splitting of the band dispersions, persisting well above the Néel temperature of bulk NaCrTe2. We argue that NaCrTe2 features a quantum-confined 2D ferromagnetic state in the topmost surface layer due to strong ferromagnetic correlation in the CrTe2 layer. Moreover, the exchange splitting and the critical temperature can be controlled by surface doping of alkali-metal atoms, suggesting the feasibility of tuning the surface ferromagnetism. Our work not only presents a simple platform for exploring tunable 2D ferromagnetism but also provides important insights into the quantum-confined low-dimensional magnetic states.
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Affiliation(s)
- Yidian Li
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Xian Du
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Junjie Wang
- Lab for Advanced Materials and Electron Microscopy, Institute of Physics, Chinese Academy of Sciences, Beijing 100083, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Runzhe Xu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Wenxuan Zhao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Kaiyi Zhai
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Jieyi Liu
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K
| | - Houke Chen
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K
| | - Yiheng Yang
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K
| | - Nicholas C Plumb
- Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Sailong Ju
- Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Ming Shi
- Photon Science Division, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
- Center for Correlated Matter and School of Physics, Zhejiang University, Hangzhou, Zhejiang 31008, China
| | - Zhongkai Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China
| | - Jian-Gang Guo
- Lab for Advanced Materials and Electron Microscopy, Institute of Physics, Chinese Academy of Sciences, Beijing 100083, China
| | - Xiaolong Chen
- Lab for Advanced Materials and Electron Microscopy, Institute of Physics, Chinese Academy of Sciences, Beijing 100083, China
| | - Yulin Chen
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
- ShanghaiTech Laboratory for Topological Physics, Shanghai 200031, China
| | - Lexian Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Frontier Science Center for Quantum Information, Beijing 100084, China
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2
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Chen J, Yang X, Zhou F, Lau YC, Feng W, Yao Y, Li Y, Jiang Y, Wang W. Colossal anomalous Hall effect in the layered antiferromagnetic EuAl 2Si 2 compound. MATERIALS HORIZONS 2024. [PMID: 38990691 DOI: 10.1039/d4mh00480a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
The anomalous Hall effect (AHE), significantly enhanced by the extrinsic mechanism, has attracted attention for its almost unlimited Hall response, which exceeds the upper limit of the Berry curvature mechanism. However, due to the high conductivity in the clean regime and weak skew scattering, it is a great challenge to obtain large anomalous Hall conductivities and large anomalous Hall angles at the same time. Here, we unveil a new magnetic metal system, EuAl2Si2, which hosts both colossal anomalous Hall conductivity (σAxy ≥ 104 Ω-1 cm-1) and large anomalous Hall angle (AHA >10%). The scaling relation suggests that the skew scattering mechanism is dominant in the colossal anomalous Hall response and gives rise to a large skew scattering constant. The large effective SOC and large magnetic moment may account for this anomaly. Our results indicate that EuAl2Si2 is a good platform to study the extrinsic AHE mechanism.
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Affiliation(s)
- Jie Chen
- School of Electronic and Information Engineering, Tiangong University, Tianjin 300387, China.
| | - Xiuxian Yang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Laboratory of Quantum Functional Materials Design and Application, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
| | - Feng Zhou
- School of Electronic and Information Engineering, Tiangong University, Tianjin 300387, China.
| | - Yong-Chang Lau
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wanxiang Feng
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Yugui Yao
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Yue Li
- School of Physical Science and Technology, Tiangong University, Tianjin 300387, China
| | - Yong Jiang
- School of Electronic and Information Engineering, Tiangong University, Tianjin 300387, China.
| | - Wenhong Wang
- School of Electronic and Information Engineering, Tiangong University, Tianjin 300387, China.
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3
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Hu G, Guo H, Lv S, Li L, Wang Y, Han Y, Pan L, Xie Y, Yu W, Zhu K, Qi Q, Xian G, Zhu S, Shi J, Bao L, Lin X, Zhou W, Yang H, Gao HJ. Room‐Temperature Antisymmetric Magnetoresistance in van der Waals Ferromagnet Fe 3GaTe 2 Nanosheets. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2403154. [PMID: 38631700 DOI: 10.1002/adma.202403154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/08/2024] [Indexed: 04/19/2024]
Abstract
Van der Waals (vdW) ferromagnetic materials have emerged as a promising platform for the development of 2D spintronic devices. However, studies to date are restricted to vdW ferromagnetic materials with low Curie temperature (Tc) and small magnetic anisotropy. Here, a chemical vapor transport method is developed to synthesize a high-quality room-temperature ferromagnet, Fe3GaTe2 (c-Fe3GaTe2), which boasts a high Tc = 356 K and large perpendicular magnetic anisotropy. Due to the planar symmetry breaking, an unconventional room-temperature antisymmetric magnetoresistance (MR) is first observed in c-Fe3GaTe2 devices with step features, manifesting as three distinctive states of high, intermediate, and low resistance with the sweeping magnetic field. Moreover, the modulation of the antisymmetric MR is demonstrated by controlling the height of the surface steps. This work provides new routes to achieve magnetic random storage and logic devices by utilizing the room-temperature thickness-controlled antisymmetric MR and further design room-temperature 2D spintronic devices based on the vdW ferromagnet c-Fe3GaTe2.
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Affiliation(s)
- Guojing Hu
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Hui Guo
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Senhao Lv
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Linxuan Li
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunhao Wang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yechao Han
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lulu Pan
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yulan Xie
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Weiqi Yu
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Ke Zhu
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qi Qi
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guoyu Xian
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shiyu Zhu
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jinan Shi
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lihong Bao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Xiao Lin
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wu Zhou
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Haitao Yang
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Hong-Jun Gao
- Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
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4
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Wang D, Wang X, Hu B, Wang J, Zou Y, Guo J, Li Z, Wang S, Li Y, Song G, Wang H, Liu Y. Strain- and Electron Doping-Induced In-Plane Spin Orientation at Room Temperature in Single-Layer CrTe 2. ACS APPLIED MATERIALS & INTERFACES 2024; 16:28791-28797. [PMID: 38783664 DOI: 10.1021/acsami.4c01034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Ferromagnets with a Curie temperature surpassing room temperature (RT) are highly sought after for advancing planar spintronics. The ultrathin CrTe2 is proposed as a promising two-dimensional (2D) ferromagnet with a Curie temperature above 300 K. However, its single-layer film is highly susceptible to specific external perturbations, leading to variable magnetic features depending on the environment. The magnetic ordering of single-layer CrTe2 remains a topic of debate, and experimental confirmation of ferromagnetic order at RT is still pending. In our study, we utilized molecular beam epitaxy to create a single-layer 1T-CrTe2 on bilayer graphene, demonstrating ferromagnetism above 300 K with in-plane magnetization through superconducting quantum interference devices (SQUID) measurements. Our density functional theory (DFT) calculations suggest that the ferromagnetic properties stem from epitaxial strain, which increases the distance between adjacent Cr atoms within the layer by about 1.6% and enhances the Cr-Te-Cr angle by approximately 1.6°. Due to its interaction with the graphene substrate, the magnetic moment transitions from an out-of-plane to an in-plane orientation, while electronic doping exceeds 1.5 e/u.c. Combining DFT calculations with in situ scanning tunneling microscopy (STM) characterizations allowed us to determine the configuration of the CrTe2 single layer on graphene. This discovery presents the first experimental proof of ferromagnetic order in single-layer CrTe2 with a Curie temperature above RT, laying the groundwork for future applications of CrTe2 single-layer-based spintronic devices.
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Affiliation(s)
- Donghui Wang
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Xin Wang
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Bingxi Hu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Jiaxuan Wang
- Department of Physics, Capital Normal University, Beijing 100048, P. R. China
| | - Yuxiao Zou
- Kunming Institute of Physics, Kunming 650223, P. R. China
| | - Jin Guo
- Department of Physics, Capital Normal University, Beijing 100048, P. R. China
| | - Zezhong Li
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Shuting Wang
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Yunliang Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guofeng Song
- Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, P. R. China
- College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hai Wang
- Department of Physics, Capital Normal University, Beijing 100048, P. R. China
| | - Ying Liu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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5
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Zhang X, Li Y, Lu Q, Xiang X, Sun X, Tang C, Mahdi M, Conner C, Cook J, Xiong Y, Inman J, Jin W, Liu C, Cai P, Santos EJG, Phatak C, Zhang W, Gao N, Niu W, Bian G, Li P, Yu D, Long S. Epitaxial Growth of Large-Scale 2D CrTe 2 Films on Amorphous Silicon Wafers With Low Thermal Budget. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311591. [PMID: 38426690 DOI: 10.1002/adma.202311591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/27/2024] [Indexed: 03/02/2024]
Abstract
2D van der Waals (vdW) magnets open landmark horizons in the development of innovative spintronic device architectures. However, their fabrication with large scale poses challenges due to high synthesis temperatures (>500 °C) and difficulties in integrating them with standard complementary metal-oxide semiconductor (CMOS) technology on amorphous substrates such as silicon oxide (SiO2) and silicon nitride (SiNx). Here, a seeded growth technique for crystallizing CrTe2 films on amorphous SiNx/Si and SiO2/Si substrates with a low thermal budget is presented. This fabrication process optimizes large-scale, granular atomic layers on amorphous substrates, yielding a substantial coercivity of 11.5 kilo-oersted, attributed to weak intergranular exchange coupling. Field-driven Néel-type stripe domain dynamics explain the amplified coercivity. Moreover, the granular CrTe2 devices on Si wafers display significantly enhanced magnetoresistance, more than doubling that of single-crystalline counterparts. Current-assisted magnetization switching, enabled by a substantial spin-orbit torque with a large spin Hall angle (85) and spin Hall conductivity (1.02 × 107 ℏ/2e Ω⁻¹ m⁻¹), is also demonstrated. These observations underscore the proficiency in manipulating crystallinity within integrated 2D magnetic films on Si wafers, paving the way for large-scale batch manufacturing of practical magnetoelectronic and spintronic devices, heralding a new era of technological innovation.
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Affiliation(s)
- Xiaoqian Zhang
- Shenzhen Institute for Quantum Science and Engineering, and Department of Physics, Southern University of Science and Technology, Shenzhen, 518055, China
- Key Laboratory of Quantum Materials and Devices of Ministry of Education, School of Physics, Southeast University, Nanjing, 211189, China
| | - Yue Li
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Qiangsheng Lu
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA
- Material Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Xueqiang Xiang
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
| | - Xiaozhen Sun
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
| | - Chunli Tang
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Muntasir Mahdi
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Clayton Conner
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA
| | - Jacob Cook
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA
| | - Yuzan Xiong
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Jerad Inman
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Physics, Oakland University, Rochester, MI, 48309, USA
| | - Wencan Jin
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, 36849, USA
- Department of Physics, Auburn University, Auburn, AL, 36849, USA
| | - Chang Liu
- Shenzhen Institute for Quantum Science and Engineering, and Department of Physics, Southern University of Science and Technology, Shenzhen, 518055, China
| | - PeiYu Cai
- Institute for Condensed Matter Physics and Complex Systems, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, UK
| | - Elton J G Santos
- Institute for Condensed Matter Physics and Complex Systems, School of Physics and Astronomy, The University of Edinburgh, Edinburgh, EH9 3FD, UK
- Higgs Centre for Theoretical Physics, The University of Edinburgh, Edinburgh, EH9 3FD, UK
- Donostia International Physics Center (DIPC), Donostia-San Sebastián, 20018, Basque Country, Spain
| | - Charudatta Phatak
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Wei Zhang
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Physics, Oakland University, Rochester, MI, 48309, USA
| | - Nan Gao
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
| | - Wei Niu
- School of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China
| | - Guang Bian
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA
| | - Peng Li
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
| | - Dapeng Yu
- Shenzhen Institute for Quantum Science and Engineering, and Department of Physics, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Shibing Long
- School of Microelectronics, University of Science and Technology of China, Hefei, 230026, China
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6
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Jin S, Wang Y, Zheng H, Dong S, Han K, Wang Z, Wang G, Jiang X, Wang X, Hong J, Huang H, Zhang Y, Xia TL, Wang X. Thickness- and Field-Dependent Magnetic Domain Evolution in van der Waals Fe 3GaTe 2. NANO LETTERS 2024; 24:5467-5473. [PMID: 38647318 DOI: 10.1021/acs.nanolett.4c00496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
The discovery of room-temperature ferromagnetism in van der Waals (vdW) materials opens new avenues for exploring low-dimensional magnetism and its applications in spintronics. Recently, the observation of the room-temperature topological Hall effect in the vdW ferromagnet Fe3GaTe2 suggests the possible existence of room-temperature skyrmions, yet skyrmions have not been directly observed. In this study, real-space imaging was employed to investigate the domain evolution of the labyrinth and skyrmion structure. First, Néel-type skyrmions can be created at room temperature. In addition, the influence of flake thickness and external magnetic field (during field cooling) on both labyrinth domains and the skyrmion lattice is unveiled. Due to the competition between magnetic anisotropy and dipole interactions, the specimen thickness significantly influences the density of skyrmions. These findings demonstrate that Fe3GaTe2 can host room-temperature skyrmions of various sizes, opening up avenues for further study of magnetic topological textures at room temperature.
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Affiliation(s)
- Shuaizhao Jin
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yiting Wang
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, China
- Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing 100872, China
| | - Haotian Zheng
- School of Automation, Beijing Institute of Technology, Beijing 100081, China
| | - Shouzhe Dong
- Advanced Research Institute of Multidisciplinary Science and School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Kun Han
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, China
- Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing 100872, China
| | - Zhan Wang
- Beijing National State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Guangcheng Wang
- School of Physics and Optoelectronic Engineering, Beijing University of Technology, Beijing 100124, China
| | - Xingang Jiang
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xiaolei Wang
- School of Physics and Optoelectronic Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jiawang Hong
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Houbing Huang
- Advanced Research Institute of Multidisciplinary Science and School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Ying Zhang
- Beijing National State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Tian-Long Xia
- Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, China
- Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education), Renmin University of China, Beijing 100872, China
| | - Xueyun Wang
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
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7
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Yang J, Wang X, Li S, Wang X, Pan M, Ai M, Yuan H, Peng X, Wang R, Li Q, Zheng F, Zhang P. Robust Two-Dimensional Ferromagnetism in Cr 5Te 8/CrTe 2 Heterostructure with Curie Temperature above 400 K. ACS NANO 2023; 17:23160-23168. [PMID: 37926969 DOI: 10.1021/acsnano.3c09654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
The discovery of ferromagnetism in two-dimensional (2D) van der Waals crystals has generated widespread interest. The seeking of robust 2D ferromagnets with high Curie temperature (Tc) is vitally important for next-generation spintronic devices. However, owing to the enhanced spin fluctuation and weak exchange interaction upon the reduced dimensionalities, the exploring of robust 2D ferromagnets with Tc > 300 K is highly demanded but remains challenging. In this work, we fabricated air-stable 2D Cr5Te8/CrTe2 vertical heterojunctions with Tc above 400 K by the chemical vapor deposition method. Transmission electron microscopy demonstrates a high-quality-crystalline epitaxial structure between tri-Cr5Te8 and 1T-CrTe2 with striped moiré patterns and a superior ambient stability over six months. A built-in dual-axis strain together with strong interfacial coupling cooperatively leads to a record-high Tc for the CrxTey family. A temperature-dependent spin-flip process induces the easy axis of magnetization to rotate from the out-of-plane to the in-plane direction, indicating a phase-dependent proximity coupling effect, rationally interpreted by first-principles calculations of the magnetic anisotropy of a tri-Cr5Te8 and 1T-CrTe2 monolayer. Our results provide a material realization of effectively enhancing the transition temperature of 2D ferromagnetism and manipulating the spin-flip of the easy axis, which will facilitate future spintronic applications.
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Affiliation(s)
- Jielin Yang
- School of Physics, Hubei University, Wuhan 430062, China
| | - Xinyu Wang
- School of Physics, Hubei University, Wuhan 430062, China
| | - Shujing Li
- College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xina Wang
- School of Physics, Hubei University, Wuhan 430062, China
| | - Minghu Pan
- School of Physics & Information Technology, Shaanxi Normal University, Xi'an 710119, China
| | - Mingzhong Ai
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Hui Yuan
- School of Physics, Hubei University, Wuhan 430062, China
| | - Xiaoniu Peng
- School of Physics, Hubei University, Wuhan 430062, China
| | - Ruilong Wang
- School of Physics, Hubei University, Wuhan 430062, China
| | - Quan Li
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Fawei Zheng
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Ping Zhang
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
- School of Physics and Physical Engineering, Qufu Normal University, Qufu 273165, China
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8
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Tan C, Liao JH, Zheng G, Algarni M, Lin JY, Ma X, Mayes ELH, Field MR, Albarakati S, Panahandeh-Fard M, Alzahrani S, Wang G, Yang Y, Culcer D, Partridge J, Tian M, Xiang B, Zhao YJ, Wang L. Room-Temperature Magnetic Phase Transition in an Electrically Tuned van der Waals Ferromagnet. PHYSICAL REVIEW LETTERS 2023; 131:166703. [PMID: 37925723 DOI: 10.1103/physrevlett.131.166703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 04/10/2023] [Accepted: 09/06/2023] [Indexed: 11/07/2023]
Abstract
Finding tunable van der Waals (vdW) ferromagnets that operate at above room temperature is an important research focus in physics and materials science. Most vdW magnets are only intrinsically magnetic far below room temperature and magnetism with square-shaped hysteresis at room temperature has yet to be observed. Here, we report magnetism in a quasi-2D magnet Cr_{1.2}Te_{2} observed at room temperature (290 K). This magnetism was tuned via a protonic gate with an electron doping concentration up to 3.8×10^{21} cm^{-3}. We observed nonmonotonic evolutions in both coercivity and anomalous Hall resistivity. Under increased electron doping, the coercivities and anomalous Hall effects (AHEs) vanished, indicating a doping-induced magnetic phase transition. This occurred up to room temperature. DFT calculations showed the formation of an antiferromagnetic (AFM) phase caused by the intercalation of protons which induced significant electron doping in the Cr_{1.2}Te_{2}. The tunability of the magnetic properties and phase in room temperature magnetic vdW Cr_{1.2}Te_{2} is a significant step towards practical spintronic devices.
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Affiliation(s)
- Cheng Tan
- Lab of Low Dimensional Magnetism and Spintronic Devices, School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Ji-Hai Liao
- Department of Physics, South China University of Technology, Guangzhou 510640, China
| | - Guolin Zheng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences (CAS), Hefei, Anhui 230031, China
| | - Meri Algarni
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
- Physics Department, Faculty of Science, Al-Baha University, Alaqiq 65779, Saudi Arabia
| | - Jia-Yi Lin
- Department of Physics, South China University of Technology, Guangzhou 510640, China
| | - Xiang Ma
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Materials Science & Engineering, CAS Key Lab of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Edwin L H Mayes
- RMIT Microscopy & Microanalysis Facility, RMIT University, Melbourne, Victoria 3000, Australia
| | - Matthew R Field
- RMIT Microscopy & Microanalysis Facility, RMIT University, Melbourne, Victoria 3000, Australia
| | - Sultan Albarakati
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
- Physics Department, Faculty of Science and Arts, University of Jeddah, P.O. Box 80200, 21589 Khulais, Saudi Arabia
| | - Majid Panahandeh-Fard
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Saleh Alzahrani
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Guopeng Wang
- Department of Physics, School of Physics and Materials Science, Anhui University, Hefei, Anhui 230601, China
| | - Yuanjun Yang
- Lab of Low Dimensional Magnetism and Spintronic Devices, School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Dimitrie Culcer
- School of Physics and ARC Centre of Excellence in Future Low-Energy Electronics Technologies, UNSW Node, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - James Partridge
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
| | - Mingliang Tian
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences (CAS), Hefei, Anhui 230031, China
- Department of Physics, School of Physics and Materials Science, Anhui University, Hefei, Anhui 230601, China
| | - Bin Xiang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Materials Science & Engineering, CAS Key Lab of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yu-Jun Zhao
- Department of Physics, South China University of Technology, Guangzhou 510640, China
| | - Lan Wang
- Lab of Low Dimensional Magnetism and Spintronic Devices, School of Physics, Hefei University of Technology, Hefei, Anhui 230009, China
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), School of Science, RMIT University, Melbourne, Victoria 3001, Australia
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9
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Man P, Huang L, Zhao J, Ly TH. Ferroic Phases in Two-Dimensional Materials. Chem Rev 2023; 123:10990-11046. [PMID: 37672768 DOI: 10.1021/acs.chemrev.3c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023]
Abstract
Two-dimensional (2D) ferroics, namely ferroelectric, ferromagnetic, and ferroelastic materials, are attracting rising interest due to their fascinating physical properties and promising functional applications. A variety of 2D ferroic phases, as well as 2D multiferroics and the novel 2D ferrovalleytronics/ferrotoroidics, have been recently predicted by theory, even down to the single atomic layers. Meanwhile, some of them have already been experimentally verified. In addition to the intrinsic 2D ferroics, appropriate stacking, doping, and defects can also artificially regulate the ferroic phases of 2D materials. Correspondingly, ferroic ordering in 2D materials exhibits enormous potential for future high density memory devices, energy conversion devices, and sensing devices, among other applications. In this paper, the recent research progresses on 2D ferroic phases are comprehensively reviewed, with emphasis on chemistry and structural origin of the ferroic properties. In addition, the promising applications of the 2D ferroics for information storage, optoelectronics, and sensing are also briefly discussed. Finally, we envisioned a few possible pathways for the future 2D ferroics research and development. This comprehensive overview on the 2D ferroic phases can provide an atlas for this field and facilitate further exploration of the intriguing new materials and physical phenomena, which will generate tremendous impact on future functional materials and devices.
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Affiliation(s)
- Ping Man
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Lingli Huang
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong 999077, P. R. China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
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10
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Wang H, Wen Y, Zhao X, Cheng R, Yin L, Zhai B, Jiang J, Li Z, Liu C, Wu F, He J. Heteroepitaxy of 2D CuCr 2 Te 4 with Robust Room-temperature Ferromagnetism. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2211388. [PMID: 36780341 DOI: 10.1002/adma.202211388] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/21/2023] [Indexed: 05/05/2023]
Abstract
Magnetic materials in 2D have attracted widespread attention for their intriguing magnetic properties. 2D magnetic heterostructures can provide unprecedented opportunities for exploring fundamental physics and novel spintronic devices. Here, the heteroepitaxial growth of ferromagnetic CuCr2 Te4 nanosheets is reported on Cr2 Te3 and mica by chemical vapor deposition. Magneto-optical Kerr effect measurements reveal the thickness-dependent ferromagnetism of CuCr2 Te4 nanosheets on mica, where a decrease of Curie temperature (TC ) from 320 to 260 K and an enhancement of perpendicular magnetic anisotropy with reducing thickness are observed. Moreover, lattice-matched heteroepitaxial ultrathin CuCr2 Te4 on Cr2 Te3 exhibits an enhanced robust ferromagnetism with TC up to 340 K due to the interfacial charge transfer. Stripe-type magnetic domains and single magnetic domain are discovered in this heterostructure with different thicknesses. The work provides a way to construct robust room-temperature 2D magnetic heterostructures for functional spintronic devices.
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Affiliation(s)
- Hao Wang
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Yao Wen
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Xiaoxu Zhao
- School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Ruiqing Cheng
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Lei Yin
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Baoxing Zhai
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Jian Jiang
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Zhongwei Li
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Chuansheng Liu
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Fengcheng Wu
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, P. R. China
| | - Jun He
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, P. R. China
- International College, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
- Hubei Luojia Laboratory, Wuhan, 430072, P. R. China
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11
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Breakdown of the scaling relation of anomalous Hall effect in Kondo lattice ferromagnet USbTe. Nat Commun 2023; 14:527. [PMID: 36720874 PMCID: PMC9889341 DOI: 10.1038/s41467-023-36221-9] [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: 09/27/2022] [Accepted: 01/18/2023] [Indexed: 02/02/2023] Open
Abstract
The interaction between strong correlation and Berry curvature is an open territory of in the field of quantum materials. Here we report large anomalous Hall conductivity in a Kondo lattice ferromagnet USbTe which is dominated by intrinsic Berry curvature at low temperatures. However, the Berry curvature induced anomalous Hall effect does not follow the scaling relation derived from Fermi liquid theory. The onset of the Berry curvature contribution coincides with the Kondo coherent temperature. Combined with ARPES measurement and DMFT calculations, this strongly indicates that Berry curvature is hosted by the flat bands induced by Kondo hybridization at the Fermi level. Our results demonstrate that the Kondo coherence of the flat bands has a dramatic influence on the low temperature physical properties associated with the Berry curvature, calling for new theories of scaling relations of anomalous Hall effect to account for the interaction between strong correlation and Berry curvature.
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12
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Zhang C, Liu C, Zhang J, Yuan Y, Wen Y, Li Y, Zheng D, Zhang Q, Hou Z, Yin G, Liu K, Peng Y, Zhang XX. Room-Temperature Magnetic Skyrmions and Large Topological Hall Effect in Chromium Telluride Engineered by Self-Intercalation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2205967. [PMID: 36245330 DOI: 10.1002/adma.202205967] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Room-temperature magnetic skyrmion materials exhibiting robust topological Hall effect (THE) are crucial for novel nano-spintronic devices. However, such skyrmion-hosting materials are rare in nature. In this study, a self-intercalated transition metal dichalcogenide Cr1+ x Te2 with a layered crystal structure that hosts room-temperature skyrmions and exhibits large THE is reported. By tuning the self-intercalate concentration, a monotonic control of Curie temperature from 169 to 333 K and a magnetic anisotropy transition from out-of-plane to the in-plane configuration are achieved. Based on the intercalation engineering, room-temperature skyrmions are successfully created in Cr1.53 Te2 with a Curie temperature of 295 K and a relatively weak perpendicular magnetic anisotropy. Remarkably, a skyrmion-induced topological Hall resistivity as large as ≈106 nΩ cm is observed at 290 K. Moreover, a sign reversal of THE is also found at low temperatures, which can be ascribed to other topological spin textures having an opposite topological charge to that of the skyrmions. Therefore, chromium telluride can be a new paradigm of the skyrmion material family with promising prospects for future device applications.
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Affiliation(s)
- Chenhui Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Chen Liu
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Junwei Zhang
- School of Materials and Energy and Electron Microscopy Centre of Lanzhou University, Lanzhou University, Lanzhou, 730000, China
| | - Youyou Yuan
- Core Labs, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Yan Wen
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Yan Li
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Dongxing Zheng
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Qiang Zhang
- Core Technology Platforms, New York University Abu Dhabi, Abu Dhabi, 129188, United Arab Emirates
| | - Zhipeng Hou
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, China
| | - Gen Yin
- Physics Department, Georgetown University, Washington, DC, 20057, USA
| | - Kai Liu
- Physics Department, Georgetown University, Washington, DC, 20057, USA
| | - Yong Peng
- School of Materials and Energy and Electron Microscopy Centre of Lanzhou University, Lanzhou University, Lanzhou, 730000, China
| | - Xi-Xiang Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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13
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Deng Y, Xiang Z, Lei B, Zhu K, Mu H, Zhuo W, Hua X, Wang M, Wang Z, Wang G, Tian M, Chen X. Layer-Number-Dependent Magnetism and Anomalous Hall Effect in van der Waals Ferromagnet Fe 5GeTe 2. NANO LETTERS 2022; 22:9839-9846. [PMID: 36475695 DOI: 10.1021/acs.nanolett.2c02696] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Realization of ferromagnetism in the two-dimensional (2D) van der Waals (vdW) crystals opens up a vital route to understand the magnetic ordering in the 2D limit and to design novel spintronics. Here, we report enriched layer-number-dependent magnetotransport properties in the vdW ferromagnet Fe5GeTe2. By studying the magnetoresistance and anomalous Hall effect (AHE) in nanoflakes with thicknesses down to monolayer, we demonstrate that while the bulk crystals exhibit soft ferromagnetism with an in-plane magnetic anisotropy, hard ferromagnetism develops upon thinning, and a perpendicular easy-axis anisotropy is realized in bilayer flakes, which is accompanied by a pronounced enhancement of AHE because of extrinsic mechanisms. For the monolayer flakes, the hard ferromagnetism is replaced by spin-glass-like behavior, in accordance with the localization effect in the 2D limit. Our results highlight the thickness-based tunability of the magnetotransport properties in the atomically thin vdW magnets that promises engineering of high-performance spintronic devices.
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Affiliation(s)
- Yazhou Deng
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, Anhui230601, China
| | - Ziji Xiang
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Bin Lei
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Kejia Zhu
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, Anhui230601, China
| | - Haimen Mu
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Weizhuang Zhuo
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Xiangyu Hua
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Mingjie Wang
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, Anhui230601, China
| | - Zhengfei Wang
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
| | - Guopeng Wang
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, Anhui230601, China
| | - Mingliang Tian
- School of Physics and Optoelectronic Engineering, Anhui University, Hefei, Anhui230601, China
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui230031, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing210093, China
| | - Xianhui Chen
- CAS Key Laboratory of Strongly Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui230026, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing210093, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, Hefei, Anhui230026, China
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14
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Liu K, Kang C, Tian J, Song Y, She L, Liu X, Zhang W. Canonical Spin Glass and the Anomalous Hall Effect in a Centrosymmetric Ferrimagnet. J Phys Chem Lett 2022; 13:10048-10055. [PMID: 36264631 DOI: 10.1021/acs.jpclett.2c02646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Centrosymmetric ferro/ferrimagnets provide an ideal arena for fundamental research due to their fascinating magnetic and structural characters. In this work, the Co0.8MnSn compound with a single hexagonal phase was successfully synthesized, and the magnetic phase transition and magnetic and electronic properties have been systematically investigated. Interestingly, Arrott plots and normalized magnetic entropy changes derived from the isothermal magnetizing curves may imply the first-order nature of the magnetic ordering transition around TC ∼ 121 K. The AC susceptibility analysis and detailed nonequilibrium dynamical studies (including magnetic aging, rejuvenation, and memory effects) reveal the canonical spin-glass state of Co0.8MnSn at lower temperature. Further, negative magnetoresistance and the anomalous Hall effect dominated by a commonly intrinsic term are obtained. Moreover, the field-dependent AC susceptibility data indicated that complicated and nontrivial magnetic spin textures should exist in the compound. These studies may open up further research opportunities in exploring emergent physical phenomena and potential applications in centrosymmetric magnets.
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Affiliation(s)
- Kai Liu
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Chaoyang Kang
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Jianjun Tian
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Yeheng Song
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Limin She
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Xiansheng Liu
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
| | - Weifeng Zhang
- Henan Key Lab of Photovoltaic Materials and Center for Topological Functional Materials, Henan University, Kaifeng475004, China
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15
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Zhang G, Guo F, Wu H, Wen X, Yang L, Jin W, Zhang W, Chang H. Above-room-temperature strong intrinsic ferromagnetism in 2D van der Waals Fe 3GaTe 2 with large perpendicular magnetic anisotropy. Nat Commun 2022; 13:5067. [PMID: 36038556 PMCID: PMC9424191 DOI: 10.1038/s41467-022-32605-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 08/08/2022] [Indexed: 11/09/2022] Open
Abstract
The absence of two-dimensional (2D) van der Waals (vdW) ferromagnetic crystals with both above-room-temperature strong intrinsic ferromagnetism and large perpendicular magnetic anisotropy (PMA) severely hinders practical applications of 2D vdW crystals in next-generation low-power magnetoelectronic and spintronic devices. Here, we report a vdW intrinsic ferromagnetic crystal Fe3GaTe2 that exhibits record-high above-room-temperature Curie temperature (Tc, ~350-380 K) for known 2D vdW intrinsic ferromagnets, high saturation magnetic moment (40.11 emu/g), large PMA energy density (~4.79 × 105 J/m3), and large anomalous Hall angle (3%) at room temperature. Such large room-temperature PMA is better than conventional widely-used ferromagnetic films like CoFeB, and one order of magnitude larger than known 2D vdW intrinsic ferromagnets. Room-temperature thickness and angle-dependent anomalous Hall devices and direct magnetic domains imaging based on Fe3GaTe2 nanosheet have been realized. This work provides an avenue for room-temperature 2D ferromagnetism, electrical control of 2D ferromagnetism and promote the practical applications of 2D-vdW-integrated spintronic devices. In isotropic two dimensional systems, long range ferromagnetic order is supressed by thermal fluctuations, and it is due to magnetic anisotropy that van der Waals magnetic materials can have ferromagnetic ordering at finite temperatures. Usually this magnetic anisotropy is relatively small, but in this manuscript Zhang et al make a two dimensional van der Waals material with exceptionally large perpendicular magnetic anisotropy and ferromagnetic ordering that exits up to 350 K.
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Affiliation(s)
- Gaojie Zhang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Fei Guo
- Liuzhou Key Lab of New-Energy Vehicle Lithium Battery, School of Microelectronics and Materials Engineering, Guangxi University of Science and Technology, Liuzhou, 545006, China
| | - Hao Wu
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xiaokun Wen
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Li Yang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wen Jin
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wenfeng Zhang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.,Shenzhen R&D Center of Huazhong University of Science and Technology (HUST), Shenzhen, 518000, China
| | - Haixin Chang
- Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China. .,Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China. .,Liuzhou Key Lab of New-Energy Vehicle Lithium Battery, School of Microelectronics and Materials Engineering, Guangxi University of Science and Technology, Liuzhou, 545006, China. .,Shenzhen R&D Center of Huazhong University of Science and Technology (HUST), Shenzhen, 518000, China.
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16
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Zhou X, Zhang RW, Yang X, Li XP, Feng W, Mokrousov Y, Yao Y. Disorder- and Topology-Enhanced Fully Spin-Polarized Currents in Nodal Chain Spin-Gapless Semimetals. PHYSICAL REVIEW LETTERS 2022; 129:097201. [PMID: 36083680 DOI: 10.1103/physrevlett.129.097201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 04/27/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Recently discovered high-quality nodal chain spin-gapless semimetals MF_{3} (M=Pd, Mn) feature an ultraclean nodal chain in the spin up channel residing right at the Fermi level and displaying a large spin gap leading to a 100% spin polarization of transport properties. Here, we investigate both intrinsic and extrinsic contributions to anomalous and spin transport in this class of materials. The dominant intrinsic origin is found to originate entirely from the gapped nodal chains without the entanglement of any other trivial bands. The side-jump mechanism is predicted to be negligibly small, but intrinsic skew scattering enhances the intrinsic Hall and Nernst signals significantly, leading to large values of respective conductivities. Our findings open a new material platform for exploring strong anomalous and spin transport properties in magnetic topological semimetals.
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Affiliation(s)
- Xiaodong Zhou
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Run-Wu Zhang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Xiuxian Yang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Xiao-Ping Li
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Wanxiang Feng
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Yuriy Mokrousov
- Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
- Institute of Physics, Johannes Gutenberg University Mainz, 55099 Mainz, Germany
| | - Yugui Yao
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China
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17
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Coughlin AL, Xie D, Zhan X, Yao Y, Deng L, Hewa-Walpitage H, Bontke T, Chu CW, Li Y, Wang J, Fertig HA, Zhang S. Van der Waals Superstructure and Twisting in Self-Intercalated Magnet with Near Room-Temperature Perpendicular Ferromagnetism. NANO LETTERS 2021; 21:9517-9525. [PMID: 34729982 DOI: 10.1021/acs.nanolett.1c02940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The emergence of van der Waals (vdW) magnets has created unprecedented opportunities to manipulate magnetism for advanced spintronics based upon all-vdW heterostructures. Among various vdW magnets, Cr1+δTe2 possesses high temperature ferromagnetism along with possible topological spin textures. As this system can support self-intercalation in the vdW gap, it is crucial to precisely pinpoint the exact intercalation to understand the intrinsic magnetism of the system. Here, we developed an iterative method to determine the self-intercalated structures and show evidence of vdW "superstructures" in individual Cr1+δTe2 nanoplates exhibiting magnetic behaviors distinct from bulk chromium tellurides. Among 26,332 possible configurations, we unambiguously identified the Cr-intercalated structure as 3-fold symmetry broken Cr1.5Te2 segmented by vdW gaps. Moreover, a twisted Cr-intercalated layered structure is observed. The spontaneous formation of twisted vdW "superstructures" not only provides insight into the diverse magnetic properties of intercalated vdW magnets but may also add complementary building blocks to vdW-based spintronics.
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Affiliation(s)
- Amanda L Coughlin
- Department of Physics, Indiana University, Bloomington, Indiana 47405, United States
| | - Dongyue Xie
- Department of Mechanical and Materials Engineering, University of Nebraska, Lincoln, Nebraska 68588, United States
| | - Xun Zhan
- Electron Microscope Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Yue Yao
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, United States
| | - Liangzi Deng
- Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, United States
| | - Heshan Hewa-Walpitage
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, United States
| | - Trevor Bontke
- Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, United States
| | - Ching-Wu Chu
- Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204, United States
- Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Yan Li
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, United States
| | - Jian Wang
- Department of Mechanical and Materials Engineering, University of Nebraska, Lincoln, Nebraska 68588, United States
| | - Herbert A Fertig
- Department of Physics, Indiana University, Bloomington, Indiana 47405, United States
- Quantum Science and Engineering Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Shixiong Zhang
- Department of Physics, Indiana University, Bloomington, Indiana 47405, United States
- Quantum Science and Engineering Center, Indiana University, Bloomington, Indiana 47405, United States
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18
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Routh S, Thirupathaiah S. Observation of Exchange Bias in Antiferromagnetic Cr 0.79Se Due to the Coexistence of Itinerant Weak Ferromagnetism at Low Temperatures. ACS OMEGA 2021; 6:28012-28018. [PMID: 34723001 PMCID: PMC8552323 DOI: 10.1021/acsomega.1c03986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
We report on the structural, electrical transport, and magnetic properties of antiferromagnetic transition-metal monochalcogenide Cr0.79Se. Different from the existing off-stoichiometric compositions, Cr0.79Se is found to be synthesized into the same NiAs-type hexagonal crystal structure as that of CrSe. Resistivity data suggest Cr0.79Se to be a Fermi-liquid-type metal at low temperatures, while at intermediate temperatures, the resistivity depends sublinearly on the temperature. Eventually, at elevated temperatures, the rate of change of resistivity rapidly decreases with increasing temperature. Magnetic measurements suggest a transition from the paramagnetic phase to an antiferromagnetic phase at a Néel temperature of 225 K. Further reduction of the sample temperature results in the coexistence of weak ferromagnetism along with the antiferromagnetic phase below 100 K. As a result, below 100 K, we identify a significant exchange bias due to the interaction between the ferro- and antiferromagnetic phases. In addition, from temperature-dependent X-ray diffraction measurements, we observe that the NiAs-type structure is stable up to as high as 600 °C.
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Affiliation(s)
- Sayan Routh
- Department of Condensed Matter
Physics and Material Sciences, S N Bose
National Centre for Basic Sciences, Kolkata, West Bengal 700106, India
| | - Setti Thirupathaiah
- Department of Condensed Matter
Physics and Material Sciences, S N Bose
National Centre for Basic Sciences, Kolkata, West Bengal 700106, India
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