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Han R, Xue X, Li P. Enhanced ferromagnetism, perpendicular magnetic anisotropy and high Curie temperature in the van der Waals semiconductor CrSeBr through strain and doping. Phys Chem Chem Phys 2024; 26:12219-12230. [PMID: 38592675 DOI: 10.1039/d4cp00855c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Two-dimensional (2D) intrinsic van der Waals ferromagnetic semiconductor (FMS) crystals with strong perpendicular magnetic anisotropy and high Curie temperature (TC) are highly desirable and hold great promise for applications in ultrahigh-speed spintronic devices. Here, we systematically investigated the effects of a biaxial strain ranging between -8% and +8% and doping with different charge carrier concentrations (≤0.7 electrons/holes per unit cell) on the electronic structure, magnetic properties, and TC of monolayer CrSeBr by combining first-principles calculations and Monte Carlo (MC) simulations. Our results demonstrate that the pristine CrSeBr monolayer possesses an intrinsic FMS character with a band gap as large as 1.03 eV, an in-plane magnetic anisotropy of 0.131 meV per unit cell, and a TC as high as 164 K. At a biaxial strain of only 0.8% and a hole density of 5.31 × 1013 cm-2, the easy magnetization axis direction transitions from in-plane to out-of-plane. More interestingly, the magnetic anisotropy energy and TC of monolayer CrSeBr are further enhanced to 1.882 meV per unit cell and 279 K, respectively, under application of a tensile biaxial strain of 8%, and the monolayer retains its semiconducting properties throughout the entire range of investigated strains. It was also found that upon doping monolayer CrSeBr with holes with a concentration of 0.7 holes per unit cell, the perpendicular magnetic anisotropy and TC are increased to 0.756 meV per cell and 235 K, respectively, and the system tends to become metallic. These findings will help to advance the application of 2D intrinsic ferromagnetic materials in spintronic devices.
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Affiliation(s)
- Ruilin Han
- School of Physics and Electronic Engineering, Shanxi University, Taiyuan 030006, China.
| | - Xiaomin Xue
- Institute of Theoretical Physics, Shanxi University, Taiyuan, 030006, China
| | - Peng Li
- School of Physics and Electronic Engineering, Shanxi University, Taiyuan 030006, China.
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2
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Han R, Xue X, Yan Y. Hole-Doping-Induced Perpendicular Magnetic Anisotropy and High Curie Temperature in a CrSX (X = Cl, Br, I) Semiconductor Monolayer. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:3105. [PMID: 38133001 PMCID: PMC10745588 DOI: 10.3390/nano13243105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023]
Abstract
A large perpendicular magnetic anisotropy and a high Curie temperature (TC) are crucial for the application of two-dimensional (2D) intrinsic ferromagnets to spintronic devices. Here, we investigated the electronic and magnetic properties of carrier-doped Van der Waals layered CrSX (X = Cl, Br, I) ferromagnets using first-principles calculations. It was found that hole doping can increase the magnitude of the magnetic anisotropy energy (MAE) and change the orientation of the easy magnetization axis at small doping amounts of 2.37 × 1013, 3.98 × 1012, and 3.33 × 1012/cm2 for CrSCl, CrSBr, and CrSI monolayers, respectively. The maximum values of the MAE reach 57, 133, and 1597 μeV/u.c. for the critical hole-doped CrSCl, CrSBr, and CrSI with spin orientation along the (001) direction, respectively. Furthermore, the Fermi energy level of lightly hole-doped CrSX (X = Cl, Br, I) moves into the spin-up valence band, leading to the CrSX (X = Cl, Br, I) magnetic semiconductor monolayer becoming first a half-metal and then a metal. In addition, the TC can also be increased up to 305, 317, and 345 K for CrSCl, CrSBr, and CrSI monolayers at doping amounts of 5.94 × 1014, 5.78 × 1014, and 5.55 × 1014/cm2, respectively. These properties suggest that the hole-doping process can render 2D CrSX (X = Cl, Br, I) monolayers remarkable materials for application to electrically controlled spintronic devices.
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Affiliation(s)
- Ruilin Han
- School of Physics and Electronic Engineering, Shanxi University, Taiyuan 030006, China
| | - Xiaomin Xue
- Institute of Theoretical Physics, Shanxi University, Taiyuan 030006, China;
| | - Yu Yan
- Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), Department of Physics, Jilin University, Changchun 130012, China;
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3
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Qian Z, Ji J, Qian L, Mao Y, Yao S, Xu J, Wang L. Interlayer coupling controlled electronic and magnetic properties of two-dimensional VOCl 2/PtTe 2 van der Waals heterostructure. RSC Adv 2023; 13:35018-35025. [PMID: 38046632 PMCID: PMC10690494 DOI: 10.1039/d3ra07237a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 11/26/2023] [Indexed: 12/05/2023] Open
Abstract
The coupling of hetero monolayers into van der Waals (vdW) heterostructures has become an effective way to obtain tunable physical and chemical properties of two dimensional (2D) materials. In this work, based on first principles calculations, we systematically explore the electronic and magnetic properties of a 2D VOCl2/PtTe2 heterostructure. Our results indicate that the ground state of the VOCl2/PtTe2 heterostructure is a ferromagnetic (FM) metal with large magnetic anisotropy energy, among which, the VOCl2 "sublayer" shows FM half metallic properties while the PtTe2 "sublayer" shows nonmagnetic metallic properties. The Curie temperature (TC) of VOCl2/PtTe2 is 111 K. Moreover, the FM-antiferromagnetic (AFM) phase transition can be obtained under biaxial strain. Our work provides an effective way to improve the performance of 2D monolayers in nano-electronic devices.
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Affiliation(s)
- Zhonghua Qian
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Jie Ji
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Liyan Qian
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Yuxuan Mao
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Suchen Yao
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Jingyi Xu
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
| | - Licheng Wang
- College of Physics Science and Technology & Microelectronics Industry Research Institute, Yangzhou University Yangzhou 225002 China
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Xiao G, Xiao WZ, Feng YX, Rong QY, Chen Q. Two-dimensional ferroelastic and ferromagnetic NiOX (X = Cl and Br) with half-metallicity and a high Curie temperature. NANOSCALE 2023; 15:17963-17971. [PMID: 37905430 DOI: 10.1039/d3nr03119e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Two-dimensional (2D) multiferroic materials with distinctive properties, such as half-metallicity, high Curie temperature (TC), and magnetoelastic coupling, hold potential applications in novel nanoscale spintronic devices, but they are rare. Using density functional theory (DFT) calculations and evolutionary algorithms, we identify new types of 2D NiOX (X = F, Cl and Br) monolayers that are stable in energy, dynamics, thermodynamics, and mechanics. Among them, NiOF is an indirect-gap antiferromagnetic (AFM) semiconductor, while NiOCl and NiOBr are half-metallic materials with ferromagnetic (FM) ordering with a TC of 671 and 692 K and in-plane magnetic anisotropy energies (MAEs) of 541 and 609 μeV per Ni along the x-axis and y-axis, respectively. Notably, ferroelasticity is another important feature of NiOCl and NiOBr monolayers with energy barriers of 234.0 and 151.5 meV per atom, respectively. Moreover, the in-plane magnetic easy axis is strongly coupled to the lattice direction. The coexistence of high ferromagnetism, ferroelasticity, half-metallicity, and magnetoelastic coupling renders NiOCl and NiOBr monolayers great potential for future nanodevices.
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Affiliation(s)
- Gang Xiao
- School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan 411104, China.
| | - Wen-Zhi Xiao
- School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan 411104, China.
| | - Ying-Xue Feng
- School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan 411104, China.
| | - Qing-Yan Rong
- School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan 411104, China.
| | - Qiao Chen
- School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan 411104, China.
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Kumari P, Rani S, Kar S, Kamalakar MV, Ray SJ. Strain-controlled spin transport in a two-dimensional (2D) nanomagnet. Sci Rep 2023; 13:16599. [PMID: 37789039 PMCID: PMC10547692 DOI: 10.1038/s41598-023-43025-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 09/18/2023] [Indexed: 10/05/2023] Open
Abstract
Semiconductors with controllable electronic transport coupled with magnetic behaviour, offering programmable spin arrangements present enticing potential for next generation intelligent technologies. Integrating and linking these two properties has been a long standing challenge for material researchers. Recent discoveries in two-dimensional (2D) magnet shows an ability to tune and control the electronic and magnetic phases at ambient temperature. Here, we illustrate controlled spin transport within the magnetic phase of the 2D semiconductor CrOBr and reveal a substantial connection between its magnetic order and charge carriers. First, we systematically analyse the strain-induced electronic behaviour of 2D CrOBr using density functional theory calculations. Our study demonstrates the phase transition from a magnetic semiconductor → half metal → magnetic metal in the material under strain application, creating intriguing spin-resolved conductance with 100% spin polarisation and spin-injection efficiency. Additionally, the spin-polarised current-voltage (I-V) trend displayed conductance variations with high strain-assisted tunability and a peak-to-valley ratio as well as switching efficiency. Our study reveals that CrOBr can exhibit highly anisotropic behaviour with perfect spin filtering, offering new implications for strain engineered magneto-electronic devices.
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Affiliation(s)
- P Kumari
- Department of Physics, Indian Institute of Technology Patna, Bihta, 801103, India
| | - S Rani
- Department of Physics, Indian Institute of Technology Patna, Bihta, 801103, India
| | - S Kar
- Department of Physics, Indian Institute of Technology Patna, Bihta, 801103, India
| | - M Venkata Kamalakar
- Department of Physics and Astronomy, Uppsala University, Box 516, 75120, Uppsala, Sweden.
| | - S J Ray
- Department of Physics, Indian Institute of Technology Patna, Bihta, 801103, India.
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Liu P, Zhang Y, Li K, Li Y, Pu Y. Recent advances in 2D van der Waals magnets: Detection, modulation, and applications. iScience 2023; 26:107584. [PMID: 37664598 PMCID: PMC10470320 DOI: 10.1016/j.isci.2023.107584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023] Open
Abstract
The emergence of two-dimensional (2D) van der Waals magnets provides an exciting platform for exploring magnetism in the monolayer limit. Exotic quantum phenomena and significant potential for spintronic applications are demonstrated in 2D magnetic crystals and heterostructures, which offer unprecedented possibilities in advanced formation technology with low power and high efficiency. In this review, we summarize recent advances in 2D van der Waals magnetic crystals. We focus mainly on van der Waals materials of truly 2D nature with intrinsic magnetism. The detection methods of 2D magnetic materials are first introduced in detail. Subsequently, the effective strategies to modulate the magnetic behavior of 2D magnets (e.g., Curie temperature, magnetic anisotropy, magnetic exchange interaction) are presented. Then, we list the applications of 2D magnets in the spintronic devices. We also highlight current challenges and broad space for the development of 2D magnets in further studies.
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Affiliation(s)
- Ping Liu
- School of Science & New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Ying Zhang
- Department of Materials Science & Engineering, CAS Key Lab of Materials for Energy Conversion, University of Science and Technology of China, Hefei 230026, China
| | - Kehan Li
- School of Science & New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Yongde Li
- School of Science & New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
| | - Yong Pu
- School of Science & New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
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He W, Yin Y, Gong Q, Evans RFL, Gutfleisch O, Xu BX, Yi M, Guo W. Giant Magnetocaloric Effect in Magnets Down to the Monolayer Limit. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300333. [PMID: 37150875 DOI: 10.1002/smll.202300333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/17/2023] [Indexed: 05/09/2023]
Abstract
2D magnets can potentially revolutionize information technology, but their potential application to cooling technology and magnetocaloric effect (MCE) in a material down to the monolayer limit remain unexplored. Herein, it is revealed through multiscale calculations the existence of giant MCE and its strain tunability in monolayer magnets such as CrX3 (X = F, Cl, Br, I), CrAX (A = O, S, Se; X = F, Cl, Br, I), and Fe3 GeTe2 . The maximum adiabatic temperature change (Δ T ad max $\Delta T_{{\rm{ad}}}^{\max }$ ), maximum isothermal magnetic entropy change, and specific cooling power in monolayer CrF3 are found as high as 11 K, 35 µJ m-2 K-1 , and 3.5 nW cm-2 under a magnetic field of 5 T, respectively. A 2% biaxial and 5% a-axis uniaxial compressive strain can remarkably increaseΔ T ad max $\Delta T_{{\rm{ad}}}^{\max }$ of CrCl3 and CrOF by 230% and 37% (up to 15.3 and 6.0 K), respectively. It is found that large net magnetic moment per unit area favors improved MCE. These findings advocate the giant-MCE monolayer magnets, opening new opportunities for magnetic cooling at nanoscale.
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Affiliation(s)
- Weiwei He
- State Key Laboratory of Mechanics and Control for Aerospace Structures & Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education & Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics (NUAA), Nanjing, 210016, China
| | - Yan Yin
- State Key Laboratory of Mechanics and Control for Aerospace Structures & Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education & Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics (NUAA), Nanjing, 210016, China
| | - Qihua Gong
- State Key Laboratory of Mechanics and Control for Aerospace Structures & Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education & Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics (NUAA), Nanjing, 210016, China
| | | | - Oliver Gutfleisch
- Institute of Materials Science, Technische Universität Darmstadt, 64287, Darmstadt, Germany
| | - Bai-Xiang Xu
- Institute of Materials Science, Technische Universität Darmstadt, 64287, Darmstadt, Germany
| | - Min Yi
- State Key Laboratory of Mechanics and Control for Aerospace Structures & Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education & Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics (NUAA), Nanjing, 210016, China
| | - Wanlin Guo
- State Key Laboratory of Mechanics and Control for Aerospace Structures & Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education & Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics (NUAA), Nanjing, 210016, China
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8
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Ghara S, Barts E, Vasin K, Kamenskyi D, Prodan L, Tsurkan V, Kézsmárki I, Mostovoy M, Deisenhofer J. Magnetization reversal through an antiferromagnetic state. Nat Commun 2023; 14:5174. [PMID: 37620350 PMCID: PMC10449929 DOI: 10.1038/s41467-023-40722-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 08/07/2023] [Indexed: 08/26/2023] Open
Abstract
Magnetization reversal in ferro- and ferrimagnets is a well-known archetype of non-equilibrium processes, where the volume fractions of the oppositely magnetized domains vary and perfectly compensate each other at the coercive magnetic field. Here, we report on a fundamentally new pathway for magnetization reversal that is mediated by an antiferromagnetic state. Consequently, an atomic-scale compensation of the magnetization is realized at the coercive field, instead of the mesoscopic or macroscopic domain cancellation in canonical reversal processes. We demonstrate this unusual magnetization reversal on the Zn-doped polar magnet Fe2Mo3O8. Hidden behind the conventional ferrimagnetic hysteresis loop, the surprising emergence of the antiferromagnetic phase at the coercive fields is disclosed by a sharp peak in the field-dependence of the electric polarization. In addition, at the magnetization reversal our THz spectroscopy studies reveal the reappearance of the magnon mode that is only present in the pristine antiferromagnetic state. According to our microscopic calculations, this unusual process is governed by the dominant intralayer coupling, strong easy-axis anisotropy and spin fluctuations, which result in a complex interplay between the ferrimagnetic and antiferromagnetic phases. Such antiferro-state-mediated reversal processes offer novel concepts for magnetization control, and may also emerge for other ferroic orders.
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Affiliation(s)
- Somnath Ghara
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany.
| | - Evgenii Barts
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Kirill Vasin
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
- Institute for Physics, Kazan (Volga region) Federal University, 420008, Kazan, Russia
| | - Dmytro Kamenskyi
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
| | - Lilian Prodan
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
| | - Vladimir Tsurkan
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
- Institute of Applied Physics, Moldova State University, MD-2028, Chişinău, Republic of Moldova
| | - István Kézsmárki
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
| | - Maxim Mostovoy
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Joachim Deisenhofer
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135, Augsburg, Germany
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Pang K, Xu X, Wei Y, Ying T, Gao B, Li W, Jiang Y. Strain-dependent magnetic ordering switching in 2D AFM ternary V-based chalcogenide monolayers. NANOSCALE 2023; 15:13420-13427. [PMID: 37547928 DOI: 10.1039/d3nr02188b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
The lack of macroscopic magnetic moments makes antiferromagnetic materials promising candidates for high-speed spintronic devices. The 2D ternary V-based chalcogenides (VXYSe4; X, Y = Al, Ga) monolayers are investigated based on the density-functional theory and Monte Carlo simulations. The results reveal that the Néel temperature of the VGa2Se4 monolayer is 18 K with zigzag2-antiferromagnetic (AFM) spin ordering. Also, the magnetic ordering of V ions in VAl2Se4 and VAlGaSe4 monolayers prefer zigzag1-AFM coupling with Néel temperature of 47 K and 33 K, respectively. The magnetic anisotropy calculations demonstrate that the easy magnetization axis of the VXYSe4 monolayers is parallel to the y axis. In addition, the VXYSe4 monolayers can be adjusted from the AFM state to the ferromagnetic (FM) state under biaxial stretching, which can be attributed to the competition between d-p-d superexchange and d-d direct exchange caused by the variation of bond length. The transition temperature of VXYSe4 monolayers can be elevated above room temperature with the help of compression strain. In particular, the in-plane magnetic anisotropy is a robust characteristic regardless of the magnitude of the applied biaxial strain. These explorations not only enrich the family of AFM monolayers with excellent stability but also provide distinctive ideas for the performance control of AFM materials and their applications in nanodevices.
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Affiliation(s)
- Kaijuan Pang
- School of Physics, Harbin Institute of Technology, Harbin 150001, China.
| | - Xiaodong Xu
- School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Yadong Wei
- School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Tao Ying
- School of Physics, Harbin Institute of Technology, Harbin 150001, China.
| | - Bo Gao
- School of Physics, Harbin Institute of Technology, Harbin 150001, China.
| | - Weiqi Li
- School of Physics, Harbin Institute of Technology, Harbin 150001, China.
| | - Yongyuan Jiang
- School of Physics, Harbin Institute of Technology, Harbin 150001, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
- Key Lab of Micro-Optics and Photonic Technology of Heilongjiang Province, Harbin 150001, China
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Zhang M, Hu Q, Huang Y, Hua C, Cheng M, Liu Z, Song S, Wang F, Lu H, He P, Cao GH, Xu ZA, Lu Y, Yang J, Zheng Y. Spin-Lattice Coupled Metamagnetism in Frustrated van der Waals Magnet CrOCl. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300964. [PMID: 37066740 DOI: 10.1002/smll.202300964] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 03/29/2023] [Indexed: 06/19/2023]
Abstract
The long-range magnetic ordering in frustrated magnetic systems is stabilized by coupling magnetic moments to various degrees of freedom, for example, by enhancing magnetic anisotropy via lattice distortion. Here, the unconventional spin-lattice coupled metamagnetic properties of atomically-thin CrOCl, a van der Waals antiferromagnet with inherent magnetic frustration rooted in the staggered square lattice, are reported. Using temperature- and angle-dependent tunneling magnetoconductance (TMC), in complementary with magnetic torque and first-principles calculations, the antiferromagnetic (AFM)-to-ferrimagnetic (FiM) metamagnetic transitions (MTs) of few-layer CrOCl are revealed to be triggered by collective magnetic moment flipping rather than the established spin-flop mechanism, when external magnetic field (H) enforces a lattice reconstruction interlocked with the five-fold periodicity of the FiM phase. The spin-lattice coupled MTs are manifested by drastic jumps in TMC, which show anomalous upshifts at the transition thresholds and persist much higher above the AFM Néel temperature. While the MTs exhibit distinctive triaxial anisotropy, reflecting divergent magnetocrystalline anisotropy of the c-axis AFM ground state, the resulting FiM phase has an a-c easy plane in which the magnetization axis is freely rotated by H. At the 2D limit, such a field-tunable FiM phase may provide unique opportunities to explore exotic emergent phenomena and novel spintronics devices.
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Affiliation(s)
- Minjie Zhang
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Qifeng Hu
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yuqiang Huang
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Chenqiang Hua
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Man Cheng
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Zhou Liu
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, P. R. China
| | - Shijie Song
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Fanggui Wang
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, P. R. China
| | - Hengzhe Lu
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Pimo He
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Guang-Han Cao
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Zhu-An Xu
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Yunhao Lu
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
| | - Jinbo Yang
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, P. R. China
| | - Yi Zheng
- Zhejiang Province Key Laboratory of Quantum Technology and Device, School of Physics, and State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, 310027, P. R. China
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11
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Wu H, Ma F, Tian Z, Liu Y, Jiao Y, Du A. Two-dimensional ferromagnetic semiconductors of monolayer BiXO 3 (X = Ru, Os) with direct band gaps, high Curie temperatures, and large magnetic anisotropy. NANOSCALE 2023. [PMID: 37409676 DOI: 10.1039/d3nr01704d] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
Two-dimensional (2D) ferromagnetic semiconductors are highly promising candidates for spintronics, but are rarely reported with direct band gaps, high Curie temperatures (Tc), and large magnetic anisotropy. Using first-principles calculations, we predict that two ferromagnetic monolayers, BiXO3 (X = Ru, Os), are such materials with a direct band gap of 2.64 and 1.69 eV, respectively. Monte Carlo simulations reveal that the monolayers show high Tc beyond 400 K. Interestingly, both BiXO3 monolayers exhibit out-of-plane magnetic anisotropy, with magnetic anisotropy energy (MAE) of 1.07 meV per Ru for BiRuO3 and 5.79 meV per Os for BiOsO3. The estimated MAE for the BiOsO3 sheet is one order of magnitude larger than that for the CrI3 monolayer (685 μeV per Cr). Based on the second-order perturbation theory, it is revealed that the large MAE of the monolayers BiRuO3 and BiOsO3 is mainly contributed by the matrix element differences between dxy and dx2-y2 and dyz and dz2 orbitals. Importantly, the ferromagnetism remains robust in 2D BiXO3 under compressive strain, while undergoing a ferromagnetic to antiferromagnetic transition under tensile strain. The intriguing electronic and magnetic properties make BiXO3 monolayers promising candidates for nanoscale electronics and spintronics.
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Affiliation(s)
- Hongbo Wu
- College of Physics, Hebei Key Laboratory of Photophysics Research and Application, Hebei Normal University, Shijiazhuang 050024, China.
| | - Fengxian Ma
- College of Physics, Hebei Key Laboratory of Photophysics Research and Application, Hebei Normal University, Shijiazhuang 050024, China.
| | - Zhixue Tian
- College of Physics, Hebei Key Laboratory of Photophysics Research and Application, Hebei Normal University, Shijiazhuang 050024, China.
| | - Ying Liu
- College of Physics, Hebei Key Laboratory of Photophysics Research and Application, Hebei Normal University, Shijiazhuang 050024, China.
| | - Yalong Jiao
- College of Physics, Hebei Key Laboratory of Photophysics Research and Application, Hebei Normal University, Shijiazhuang 050024, China.
| | - Aijun Du
- School of Chemistry and Physics, Queensland University of Technology, Gardens Point Campus, Brisbane, QLD 4000, Australia
- Centre for Materials Science, Queensland University of Technology, Gardens Point Campus, Brisbane, QLD 4000, Australia
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12
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Qi S, Chen D, Chen K, Liu J, Chen G, Luo B, Cui H, Jia L, Li J, Huang M, Song Y, Han S, Tong L, Yu P, Liu Y, Wu H, Wu S, Xiao J, Shindou R, Xie XC, Chen JH. Giant electrically tunable magnon transport anisotropy in a van der Waals antiferromagnetic insulator. Nat Commun 2023; 14:2526. [PMID: 37130859 PMCID: PMC10154397 DOI: 10.1038/s41467-023-38172-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 04/19/2023] [Indexed: 05/04/2023] Open
Abstract
Anisotropy is a manifestation of lowered symmetry in material systems that have profound fundamental and technological implications. For van der Waals magnets, the two-dimensional (2D) nature greatly enhances the effect of in-plane anisotropy. However, electrical manipulation of such anisotropy as well as demonstration of possible applications remains elusive. In particular, in-situ electrical modulation of anisotropy in spin transport, vital for spintronics applications, has yet to be achieved. Here, we realized giant electrically tunable anisotropy in the transport of second harmonic thermal magnons (SHM) in van der Waals anti-ferromagnetic insulator CrPS4 with the application of modest gate current. Theoretical modeling found that 2D anisotropic spin Seebeck effect is the key to the electrical tunability. Making use of such large and tunable anisotropy, we demonstrated multi-bit read-only memories (ROMs) where information is inscribed by the anisotropy of magnon transport in CrPS4. Our result unveils the potential of anisotropic van der Waals magnons for information storage and processing.
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Affiliation(s)
- Shaomian Qi
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Di Chen
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Kangyao Chen
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Jianqiao Liu
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Guangyi Chen
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Bingcheng Luo
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Hang Cui
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Linhao Jia
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Jiankun Li
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Miaoling Huang
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Yuanjun Song
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Shiyi Han
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Lianming Tong
- College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Peng Yu
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Yi Liu
- Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing, China
| | - Hongyu Wu
- Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, China
| | - Shiwei Wu
- Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai, China
| | - Jiang Xiao
- Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai, China
| | - Ryuichi Shindou
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
| | - X C Xie
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China
- Hefei National Laboratory, Hefei, China
| | - Jian-Hao Chen
- International Center of Quantum Materials, School of Physics, Peking University, Beijing, China.
- Beijing Academy of Quantum Information Sciences, Beijing, China.
- Hefei National Laboratory, Hefei, China.
- Key Laboratory for the Physics and Chemistry of Nanodevices, Peking University, Beijing, China.
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13
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Niu Y, Lv H, Wu X, Yang J. Electric-Field Control of Spin Polarization above Room Temperature in Single-Layer A-Type Antiferromagnetic Semiconductor. J Phys Chem Lett 2023; 14:4042-4049. [PMID: 37093651 DOI: 10.1021/acs.jpclett.3c00883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Two-dimensional (2D) antiferromagnets have drawn great interest for absence of stray fields in antiferromagnetic (AFM) spintronics. However, it remains challenging to manipulate their spin polarization above room temperature for practical applications. Herein, a general strategy is reported to realize the control of spin polarization above room temperature in 2D A-type AFM semiconductors by external electric field based on first-principles calculations, exemplified by transition metal monohalide MnCl and carbide MXenes Cr2CX2 (X = F, Cl, OH). It shows that 100% spin polarization can be induced around Fermi level with spin splitting gap related to the spatial distribution of spin density in real space. Meanwhile, the Neél temperature of 2D MnCl and Cr2CF2 remains above room temperature under external electric field up to 0.6 V/Å. This study exhibits the potential for application of 2D AFM semiconductors in electric-field-controlled spintronics.
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Affiliation(s)
- Yijie Niu
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Science, CAS Center for Excellence in Nanoscience, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Haifeng Lv
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Science, CAS Center for Excellence in Nanoscience, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiaojun Wu
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Science, CAS Center for Excellence in Nanoscience, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
- Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230088, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Jinlong Yang
- CAS Key Laboratory of Materials for Energy Conversion, School of Chemistry and Materials Science, CAS Center for Excellence in Nanoscience, and Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), University of Science and Technology of China, Hefei, Anhui 230026, China
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
- Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230088, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
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14
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Liu C, Li Z, Hu J, Duan H, Wang C, Cai L, Feng S, Wang Y, Liu R, Hou D, Liu C, Zhang R, Zhu L, Niu Y, Zakharov AA, Sheng Z, Yan W. Probing the Néel-Type Antiferromagnetic Order and Coherent Magnon-Exciton Coupling in Van Der Waals VPS 3. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2300247. [PMID: 37071057 DOI: 10.1002/adma.202300247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/01/2023] [Indexed: 06/13/2023]
Abstract
2D van der Waals (vdW) antiferromagnets have received intensive attention due to their terahertz resonance, multilevel magnetic-order states, and ultrafast spin dynamics. However, accurately identifying their magnetic configuration still remains a challenge owing to the lack of net magnetization and insensitivity to external fields. In this work, the Néel-type antiferromagnetic (AFM) order in 2D antiferromagnet VPS3 with the out-of-plane anisotropy, which is demonstrated by the temperature-dependent spin-phonon coupling and second-harmonic generation (SHG), is experimentally probed. This long-range AFM order even persists at the ultrathin limit. Furthermore, strong interlayer exciton-magnon coupling (EMC) upon the Néel-type AFM order is detected based on the monolayer WSe2 /VPS3 heterostructure, which induces an enhanced excitonic state and further certifies the Néel-type AFM order of VPS3 . The discovery provides optical routes as the novel platform to study 2D antiferromagnets and promotes their potential applications in magneto-optics and opto-spintronic devices.
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Affiliation(s)
- Chaocheng Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Zhi Li
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Jiyu Hu
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, China
| | - Hengli Duan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Chao Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Liang Cai
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Sihua Feng
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Yao Wang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - Ruiqi Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
| | - De Hou
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Caixing Liu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Ranran Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Lin Zhu
- MAX IV Laboratory, Lund University, Lund, 22100, Sweden
| | - Yuran Niu
- MAX IV Laboratory, Lund University, Lund, 22100, Sweden
| | | | - Zhigao Sheng
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Wensheng Yan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, 230026, China
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15
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Yang K, Gao X, Wang Y, Zhang T, Gao Y, Lu X, Zhang S, Liu J, Gu P, Luo Z, Zheng R, Cao S, Wang H, Sun X, Watanabe K, Taniguchi T, Li X, Zhang J, Dai X, Chen JH, Ye Y, Han Z. Unconventional correlated insulator in CrOCl-interfaced Bernal bilayer graphene. Nat Commun 2023; 14:2136. [PMID: 37059725 PMCID: PMC10104821 DOI: 10.1038/s41467-023-37769-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 03/30/2023] [Indexed: 04/16/2023] Open
Abstract
The realization of graphene gapped states with large on/off ratios over wide doping ranges remains challenging. Here, we investigate heterostructures based on Bernal-stacked bilayer graphene (BLG) atop few-layered CrOCl, exhibiting an over-1-GΩ-resistance insulating state in a widely accessible gate voltage range. The insulating state could be switched into a metallic state with an on/off ratio up to 107 by applying an in-plane electric field, heating, or gating. We tentatively associate the observed behavior to the formation of a surface state in CrOCl under vertical electric fields, promoting electron-electron (e-e) interactions in BLG via long-range Coulomb coupling. Consequently, at the charge neutrality point, a crossover from single particle insulating behavior to an unconventional correlated insulator is enabled, below an onset temperature. We demonstrate the application of the insulating state for the realization of a logic inverter operating at low temperatures. Our findings pave the way for future engineering of quantum electronic states based on interfacial charge coupling.
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Affiliation(s)
- Kaining Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, PR China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, PR China
| | - Xiang Gao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, PR China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, PR China
| | - Yaning Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
- School of Material Science and Engineering, University of Science and Technology of China, Anhui, China
| | - Tongyao Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, PR China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, PR China
| | - Yuchen Gao
- Collaborative Innovation Center of Quantum Matter, Beijing, China
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, China
| | - Xin Lu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, China.
| | - Shihao Zhang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, China
| | - Jianpeng Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, China
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai, China
| | - Pingfan Gu
- Collaborative Innovation Center of Quantum Matter, Beijing, China
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, China
| | - Zhaoping Luo
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Runjie Zheng
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
| | - Shimin Cao
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China
- Beijing Academy of Quantum Information Sciences, Beijing, China
| | - Hanwen Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Xingdan Sun
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Xiuyan Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Jing Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, PR China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, PR China
| | - Xi Dai
- Materials Department, University of California, Santa Barbara, CA, USA.
- Department of Physics, The Hongkong University of Science and Technology, Hong Kong, China.
| | - Jian-Hao Chen
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, China.
- Beijing Academy of Quantum Information Sciences, Beijing, China.
- Key Laboratory for the Physics and Chemistry of Nanodevices, Peking University, Beijing, China.
- Hefei National Laboratory, Hefei, China.
| | - Yu Ye
- Collaborative Innovation Center of Quantum Matter, Beijing, China.
- State Key Lab for Mesoscopic Physics and Frontiers Science Center for Nano-Optoelectronics, School of Physics, Peking University, Beijing, China.
| | - Zheng Han
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan, PR China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, PR China.
- Liaoning Academy of Materials, Shenyang, China.
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16
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Cicirello G, Wang M, Sam QP, Hart JL, Williams NL, Yin H, Cha JJ, Wang J. Two-Dimensional Violet Phosphorus P 11: A Large Band Gap Phosphorus Allotrope. J Am Chem Soc 2023; 145:8218-8230. [PMID: 36996286 DOI: 10.1021/jacs.3c01766] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2023]
Abstract
The discovery of novel large band gap two-dimensional (2D) materials with good stability and high carrier mobility will innovate the next generation of electronics and optoelectronics. A new allotrope of 2D violet phosphorus P11 was synthesized via a salt flux method in the presence of bismuth. Millimeter-sized crystals of violet-P11 were collected after removing the salt flux with DI water. From single-crystal X-ray diffraction, the crystal structure of violet-P11 was determined to be in the monoclinic space group C2/c (no. 15) with unit cell parameters of a = 9.166(6) Å, b = 9.121(6) Å, c = 21.803(14)Å, β = 97.638(17)°, and a unit cell volume of 1807(2) Å3. The structure differences between violet-P11, violet-P21, and fibrous-P21 are discussed. The violet-P11 crystals can be mechanically exfoliated down to a few layers (∼6 nm). Photoluminescence and Raman measurements reveal the thickness-dependent nature of violet-P11, and exfoliated violet-P11 flakes were stable in ambient air for at least 1 h, exhibiting moderate ambient stability. The bulk violet-P11 crystals exhibit excellent stability, being stable in ambient air for many days. The optical band gap of violet-P11 bulk crystals is 2.0(1) eV measured by UV-Vis and electron energy-loss spectroscopy measurements, in agreement with density functional theory calculations which predict that violet-P11 is a direct band gap semiconductor with band gaps of 1.8 and 1.9 eV for bulk and monolayer, respectively, and with a high carrier mobility. This band gap is the largest among the known single-element 2D layered bulk crystals and thus attractive for various optoelectronic devices.
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Affiliation(s)
- Gary Cicirello
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
| | - Mengjing Wang
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, United States
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Quynh P Sam
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - James L Hart
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Natalie L Williams
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Huabing Yin
- Institute for Computational Materials Science, Joint Center for Theoretical Physics, and International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, School of Physics and Electronics, Henan University, Kaifeng 475004, China
| | - Judy J Cha
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06520, United States
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Jian Wang
- Department of Chemistry and Biochemistry, Wichita State University, Wichita, Kansas 67260, United States
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17
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Klein J, Pingault B, Florian M, Heißenbüttel MC, Steinhoff A, Song Z, Torres K, Dirnberger F, Curtis JB, Weile M, Penn A, Deilmann T, Dana R, Bushati R, Quan J, Luxa J, Sofer Z, Alù A, Menon VM, Wurstbauer U, Rohlfing M, Narang P, Lončar M, Ross FM. The Bulk van der Waals Layered Magnet CrSBr is a Quasi-1D Material. ACS NANO 2023; 17:5316-5328. [PMID: 36926838 DOI: 10.1021/acsnano.2c07316] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Correlated quantum phenomena in one-dimensional (1D) systems that exhibit competing electronic and magnetic order are of strong interest for the study of fundamental interactions and excitations, such as Tomonaga-Luttinger liquids and topological orders and defects with properties completely different from the quasiparticles expected in their higher-dimensional counterparts. However, clean 1D electronic systems are difficult to realize experimentally, particularly for magnetically ordered systems. Here, we show that the van der Waals layered magnetic semiconductor CrSBr behaves like a quasi-1D material embedded in a magnetically ordered environment. The strong 1D electronic character originates from the Cr-S chains and the combination of weak interlayer hybridization and anisotropy in effective mass and dielectric screening, with an effective electron mass ratio of mXe/mYe ∼ 50. This extreme anisotropy experimentally manifests in strong electron-phonon and exciton-phonon interactions, a Peierls-like structural instability, and a Fano resonance from a van Hove singularity of similar strength to that of metallic carbon nanotubes. Moreover, because of the reduced dimensionality and interlayer coupling, CrSBr hosts spectrally narrow (1 meV) excitons of high binding energy and oscillator strength that inherit the 1D character. Overall, CrSBr is best understood as a stack of weakly hybridized monolayers and appears to be an experimentally attractive candidate for the study of exotic exciton and 1D-correlated many-body physics in the presence of magnetic order.
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Affiliation(s)
- Julian Klein
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Benjamin Pingault
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- QuTech, Delft University of Technology, 2600 GA Delft, The Netherlands
| | - Matthias Florian
- Department of Electrical and Computer Engineering, Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Alexander Steinhoff
- Institut für Theoretische Physik, Universität Bremen, P.O. Box 330 440, 28334 Bremen, Germany
- Bremen Center for Computational Materials Science, University of Bremen, 28359 Bremen, Germany
| | - Zhigang Song
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Kierstin Torres
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Florian Dirnberger
- Department of Physics, City College of New York, New York, New York 10031, United States
| | - Jonathan B Curtis
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- College of Letters and Science, UCLA, Los Angeles, California 90095 United States
| | - Mads Weile
- Center for Visualizing Catalytic Processes (VISION), Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Aubrey Penn
- MIT.nano, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Thorsten Deilmann
- Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Rami Dana
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Rezlind Bushati
- Department of Physics, City College of New York, New York, New York 10031, United States
- Department of Physics, The Graduate Center, City University of New York, New York, New York 10016, United States
| | - Jiamin Quan
- Photonics Initiative, CUNY Advanced Science Research Center, New York, New York 10031, United States
- Physics Program, Graduate Center, City University of New York, New York, New York 10026, United States
| | - Jan Luxa
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Zdeněk Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Andrea Alù
- Photonics Initiative, CUNY Advanced Science Research Center, New York, New York 10031, United States
- Physics Program, Graduate Center, City University of New York, New York, New York 10026, United States
| | - Vinod M Menon
- Department of Physics, City College of New York, New York, New York 10031, United States
- Department of Physics, The Graduate Center, City University of New York, New York, New York 10016, United States
| | - Ursula Wurstbauer
- Institute of Physics and Center for Nanotechnology, University of Münster, 48149 Münster, Germany
| | - Michael Rohlfing
- Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Prineha Narang
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- College of Letters and Science, UCLA, Los Angeles, California 90095 United States
| | - Marko Lončar
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Frances M Ross
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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18
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Feng Y, Wang Z, Liu N, Yang Q. First-principles prediction of two-dimensional MnOX (X = Cl, Br) monolayers: the half-metallic multiferroics with magnetoelastic coupling. NANOSCALE 2023; 15:4546-4552. [PMID: 36757295 DOI: 10.1039/d2nr05764f] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Two-dimensional (2D) multiferroics have attracted extensive attention in recent years due to their potential applications in nano-electrical devices such as nonvolatile memory and magnetic sensors. However, 2D multiferroic materials with intrinsic ferromagnetism and ferroelasticity are very rare and most of them have low Curie temperatures. Herein, by performing the first-principles calculations, we systematically investigated the electronic structure and the magnetic properties of the MnOX (X = Cl, Br) monolayers. We demonstrated that the MnOX monolayers were intrinsic half-metallic multiferroics with the coexistence of ferromagnetism and ferroelasticity. The Curie temperatures evaluated from Monte Carlo simulations based on the Heisenberg model were about 220 K for MnOCl and 210 K for MnOBr, which could be further enhanced to 235 K and 230 K by 3% tensile strain. Moreover, their ground states exhibited significant big magnetic anisotropy energies of about 0.59 meV along the z-axis for MnOCl and 0.62 meV along the y-axis for MnOBr per unit cell. The in-plane magnetic easy axis of the MnOBr monolayer can be modulated by the ferroelastic switching due to the robust magnetoelastic coupling. These findings highlight that the MnOX monolayers (with 100% spin polarizability and high Curie temperature) are good candidates for next-generation multifunctional nanodevices.
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Affiliation(s)
- Yulin Feng
- College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China.
| | - Zilong Wang
- College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China.
| | - Na Liu
- College of Physics and Electronic Science, Hubei Normal University, Huangshi 435002, China.
| | - Qing Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
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19
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Liu W, Guo X, Schwartz J, Xie H, Dhale NU, Sung SH, Kondusamy ALN, Wang X, Zhao H, Berman D, Hovden R, Zhao L, Lv B. A Three-Stage Magnetic Phase Transition Revealed in Ultrahigh-Quality van der Waals Bulk Magnet CrSBr. ACS NANO 2022; 16:15917-15926. [PMID: 36149801 DOI: 10.1021/acsnano.2c02896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
van der Waals (vdW) magnets are receiving ever-growing attention nowadays due to their significance in both fundamental research on low-dimensional magnetism and potential applications in spintronic devices. The high crystalline quality of vdW magnets is the key to maintaining intrinsic magnetic and electronic properties, especially when exfoliated down to the two-dimensional limit. Here, ultrahigh-quality air-stable vdW CrSBr crystals are synthesized using the direct solid-vapor synthesis method. The high single crystallinity and spatial homogeneity have been thoroughly evidenced at length scales from submm to atomic resolution by X-ray diffraction, second harmonic generation, and scanning transmission electron microscopy. More importantly, specific heat measurements of ultrahigh-quality CrSBr crystals show three thermodynamic anomalies at 185, 156, and 132 K, revealing a stage-by-stage development of the magnetic order upon cooling, which is also corroborated with the magnetization and transport results. Our ultrahigh-quality CrSBr can further be exfoliated down to monolayers and bilayers easily, providing the building blocks of heterostructures for spintronic and magneto-optoelectronic applications.
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Affiliation(s)
- Wenhao Liu
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Xiaoyu Guo
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jonathan Schwartz
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hongchao Xie
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Nikhil Uday Dhale
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Suk Hyun Sung
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | | | - Xiqu Wang
- Department of Chemistry, University of Houston, Houston, Texas 77004, United States
| | - Haonan Zhao
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Diana Berman
- Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203, United States
| | - Robert Hovden
- Department of Material Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Liuyan Zhao
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Bing Lv
- Department of Physics, The University of Texas at Dallas, Richardson, Texas 75080, United States
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080 United States
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20
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Villalpando G, Ferrenti AM, Singha R, Song X, Cheng G, Yao N, Schoop LM. Chemical Exfoliation toward Magnetic 2D VOCl Monolayers. ACS NANO 2022; 16:13814-13820. [PMID: 35977071 DOI: 10.1021/acsnano.2c01858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The diversification of magnetic two-dimensional (2D) materials holds the key to the further development of advanced technologies, such as spintronic devices and efficient data storage. However, the search for intrinsic magnetism down to the 2D limit is severely limited by the ability to reliably exfoliate large, air-stable nanosheets. Chemical exfoliation, a relatively underutilized method for delamination, offers many advantages, including a high degree of adaptability and higher yields of uniformly exfoliated materials. van der Waals (vdW) materials, in particular the family of transition-metal oxyhalides, are ideal candidates for chemical exfoliation due to their large interlayer spacing and the wide variety of interesting magnetic properties they exhibit. In this study, we employ a chemical exfoliation method to delaminate the layered antiferromagnet vanadium oxychloride (VOCl) down to the monolayer limit. The resulting nansoheets have lateral sizes of up to 20 μm, are air-stable, and can be easily isolated. Magnetic characterization was performed throughout the exfoliation process, tracking the changes in magnetic behavior among bulk VOCl, its lithiated intercalate, and the restacked nanosheet pellet. The results from this work demonstrate the potential of chemical exfoliation, along with illustrating the effects of low dimensionality on magnetic properties.
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Affiliation(s)
- Graciela Villalpando
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Austin M Ferrenti
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Ratnadwip Singha
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Xiaoyu Song
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Guangming Cheng
- Princeton Institute for Science and Technology of Materials, Princeton, New Jersey 08544, United States
| | - Nan Yao
- Princeton Institute for Science and Technology of Materials, Princeton, New Jersey 08544, United States
| | - Leslie M Schoop
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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21
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Zeng Y, Gu P, Zhao Z, Zhang B, Lin Z, Peng Y, Li W, Zhao W, Leng Y, Tan P, Yang T, Zhang Z, Song Y, Yang J, Ye Y, Tian K, Hou Y. 2D FeOCl: A Highly In-Plane Anisotropic Antiferromagnetic Semiconductor Synthesized via Temperature-Oscillation Chemical Vapor Transport. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108847. [PMID: 35102635 DOI: 10.1002/adma.202108847] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/30/2022] [Indexed: 06/14/2023]
Abstract
2D van der Waals (vdW) transition-metal oxyhalides with low symmetry, novel magnetism, and good stability provide a versatile platform for conducting fundamental research and developing spintronics. Antiferromagnetic FeOCl has attracted significant interest owing to its unique semiconductor properties and relatively high Néel temperature. Herein, good-quality centimeter-scale FeOCl single crystals are controllably synthesized using the universal temperature-oscillation chemical vapor transport (TO-CVT) method. The crystal structure, bandgap, and anisotropic behavior of the 2D FeOCl are explored in detail. The absorption spectrum and electrical measurements reveal that 2D FeOCl is a semiconductor with an optical bandgap of ≈2.1 eV and a resistivity of ≈10-1 Ω m at 295 K, and the bandgap increases with decreasing thickness. Strong in-plane optical and electrical anisotropies are observed in 2D FeOCl flakes, and the maximum resistance anisotropic ratio reaches 2.66 at 295 K. Additionally, the lattice vibration modes are studied through temperature-dependent Raman spectra and first-principles density functional calculations. A significant decrease in the Raman frequencies below the Néel temperature is observed, which results from the strong spin-phonon coupling effect in 2D FeOCl. This study provides a high-quality low-symmetry vdW magnetic candidate for miniaturized spintronics.
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Affiliation(s)
- Yi Zeng
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Pingfan Gu
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
| | - Zijing Zhao
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Biao Zhang
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Zhongchong Lin
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
| | - Yuxuan Peng
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
| | - Wei Li
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Wanting Zhao
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Yuchen Leng
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Pingheng Tan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, China
| | - Teng Yang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Zhidong Zhang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China
| | - Youting Song
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jinbo Yang
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
| | - Yu Ye
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
| | - Kesong Tian
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
| | - Yanglong Hou
- School of Materials Science and Engineering, Beijing Key Laboratory for Magnetoelectric Materials and Devices, Beijing Innovation Centre for Engineering Science and Advanced Technology, Peking University, Beijing, 100871, China
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22
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Zhang T, Zhang Y, Huang M, Li B, Sun Y, Qu Z, Duan X, Jiang C, Yang S. Tuning the Exchange Bias Effect in 2D van der Waals Ferro-/Antiferromagnetic Fe 3 GeTe 2 /CrOCl Heterostructures. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105483. [PMID: 35238180 PMCID: PMC9009105 DOI: 10.1002/advs.202105483] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/14/2022] [Indexed: 06/01/2023]
Abstract
The exchange bias effect is extremely expected in 2D van der Waals (vdW) ferromagnetic (FM)/antiferromagnetic (AFM) heterostructures due to the high-quality interface. CrOCl possesses strong magnetic anisotropy at 2D limit, and is an ideal antiferromagnet for constructing FM/AFM heterostructures to explore the exchange bias effect. Here, the exchange bias effect in Fe3 GeTe2 (FGT)/CrOCl heterostructures through both anomalous Hall effect (AHE) and reflective magnetic circular dichroism (RMCD) measurements is studied. In the AHE measurements, the exchange bias field (HEB ) at 3 K exhibits a distinct increase from ≈150 Oe to ≈450 Oe after air exposure, and such variation is attributed to the formation of an oxidized layer in FGT by analyzing the cross-sectional microstructure. The HEB is successfully tuned by changing the FGT/CrOCl thickness and the cooling field. Furthermore, a larger HEB of ≈750 Oe at 1.7 K in FGT/CrOCl heterostructure through RMCD measurements is observed, and it is proposed that the larger HEB in RMCD measurements is related to the distribution of uncompensated spins at the interface. This work reveals several intriguing phenomena of the exchange bias effect in 2D vdW magnetic systems, which paves the way for the study of related spintronic devices.
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Affiliation(s)
- Tianle Zhang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
| | - Yujun Zhang
- Department of PhysicsSouthern University of Science and TechnologyShenzhenGuangdong518055P. R. China
| | - Mingyuan Huang
- Department of PhysicsSouthern University of Science and TechnologyShenzhenGuangdong518055P. R. China
| | - Bo Li
- Hunan Key Laboratory of Two‐Dimensional MaterialsSchool of Physics and ElectronicsHunan UniversityChangshaHunan410082P. R. China
| | - Yinghui Sun
- Beijing Key Laboratory for Magneto‐Photoelectrical Composite and Interface ScienceSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing100083P. R. China
| | - Zhe Qu
- Anhui Key Laboratory of Condensed Matter Physics at Extreme ConditionsHigh Magnetic Field LaboratoryChinese Academy of SciencesHefeiAnhui230031P. R. China
| | - Xidong Duan
- State Key Laboratory for Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangshaHunan419982P. R. China
| | - Chengbao Jiang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
| | - Shengxue Yang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
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23
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Gu P, Sun Y, Wang C, Peng Y, Zhu Y, Cheng X, Yuan K, Lyu C, Liu X, Tan Q, Zhang Q, Gu L, Wang Z, Wang H, Han Z, Watanabe K, Taniguchi T, Yang J, Zhang J, Ji W, Tan PH, Ye Y. Magnetic Phase Transitions and Magnetoelastic Coupling in a Two-Dimensional Stripy Antiferromagnet. NANO LETTERS 2022; 22:1233-1241. [PMID: 35041438 DOI: 10.1021/acs.nanolett.1c04373] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Materials with a quasi-one-dimensional stripy magnetic order often exhibit low crystal and magnetic symmetries, thus allowing the presence of various energy coupling terms and giving rise to macroscopic interplay between spin, charge, and phonon. In this work, we performed optical, electrical and magnetic characterizations combined with first-principles calculations on a van der Waals antiferromagnetic insulator chromium oxychloride (CrOCl). We detected the subtle phase transition behaviors of exfoliated CrOCl under varying temperature and magnetic field and clarified its controversial spin structures. We found that the antiferromagnetism and its air stability persist down to few-layer samples, making it a promising candidate for future 2D spintronic devices. Additionally, we verified the magnetoelastic coupling effect in CrOCl, allowing for the potential manipulation of the magnetic states via electric field or strain. These virtues of CrOCl provide us with an ideal platform for fundamental research on spin-charge, spin-phonon coupling, and spin-interactions.
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Affiliation(s)
- Pingfan Gu
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Yujia Sun
- State Key Laboratory of 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
| | - Cong Wang
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing, 100872, China
| | - Yuxuan Peng
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Yaozheng Zhu
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Xing Cheng
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Kai Yuan
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Chao Lyu
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Xuelu Liu
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Qinghai Tan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhi Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Hanwen Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Zheng Han
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Optoelectronics, Shanxi University, Taiyuan 03006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 03006, China
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Jinbo Yang
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
| | - Jun Zhang
- State Key Laboratory of 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
| | - Wei Ji
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing, 100872, China
| | - Ping-Heng Tan
- State Key Laboratory of 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
| | - Yu Ye
- State Key Laboratory for Mesoscopic Physics, Nano-optoelectronics Frontier Center of the Ministry of Education, School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
- Yangtze Delta Institute of Optoelectronics, Peking University, Nantong 226010, Jiangsu China
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24
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Rahman S, Torres JF, Khan AR, Lu Y. Recent Developments in van der Waals Antiferromagnetic 2D Materials: Synthesis, Characterization, and Device Implementation. ACS NANO 2021; 15:17175-17213. [PMID: 34779616 DOI: 10.1021/acsnano.1c06864] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Magnetism in two dimensions is one of the most intriguing and alluring phenomena in condensed matter physics. Atomically thin 2D materials have emerged as a promising platform for exploring magnetic properties, leading to the development of essential technologies such as supercomputing and data storage. Arising from spin and charge dynamics in elementary particles, magnetism has also unraveled promising advances in spintronic devices and spin-dependent optoelectronics and photonics. Recently, antiferromagnetism in 2D materials has received extensive attention, leading to significant advances in their understanding and emerging applications; such materials have zero net magnetic moment yet are internally magnetic. Several theoretical and experimental approaches have been proposed to probe, characterize, and modulate the magnetic states efficiently in such systems. This Review presents the latest developments and current status for tuning the magnetic properties in distinct 2D van der Waals antiferromagnets. Various state-of-the-art optical techniques deployed to investigate magnetic textures and dynamics are discussed. Furthermore, device concepts based on antiferromagnetic spintronics are scrutinized. We conclude with remarks on related challenges and technological outlook in this rapidly expanding field.
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Affiliation(s)
- Sharidya Rahman
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia
| | - Juan F Torres
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia
| | - Ahmed Raza Khan
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia
| | - Yuerui Lu
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, ACT 2601, Australia
- ARC Centre for Quantum Computation and Communication Technology, Department of Quantum Science, Research School of Physics and Engineering, The Australian National University, Acton, ACT 2601, Australia
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET), ANU node, Canberra, ACT 2601, Australia
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25
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Yao Y, Zhan X, Sendeku MG, Yu P, Dajan FT, Zhu C, Li N, Wang J, Wang F, Wang Z, He J. Recent progress on emergent two-dimensional magnets and heterostructures. NANOTECHNOLOGY 2021; 32:472001. [PMID: 34315143 DOI: 10.1088/1361-6528/ac17fd] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Intrinsic two-dimensional (2D) magnetic materials own strong long-range magnetism while their characteristics of the ultrathin thickness and smooth surface provide an ideal platform for manipulating the magnetic properties at 2D limit. This makes them to be potential candidates in various spintronic applications compared to their corresponding bulk counterparts. The discovery of magnetic ordering in 2D CrI3and Gr2Ge2Te6nanostructures stimulated tremendous research interest in both experimental and theoretical studies on various intrinsic magnets at 2D limit. This review gives a comprehensive overview of the recent progress on the emergent 2D magnets and heterostructures. Firstly, several kinds of typical 2D magnetic materials discovered in the last few years and their fabrication methods are summarized in detail. Secondly, the current strategies for manipulating magnetic properties in 2D materials are further discussed. Then, the recent advances on the construction of representative van der Waals magnetic heterostructures and their respective performance are provided. With the hope of motivating the researchers in this area, we finally offered the challenges and outlook on 2D magnetism.
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Affiliation(s)
- Yuyu Yao
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Sino-Danish Center for Education, Beijing 100049, People's Republic of China
| | - Xueying Zhan
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Marshet Getaye Sendeku
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Peng Yu
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Fekadu Tsegaye Dajan
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Chuanchao Zhu
- Institute for Quantum Information & State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - Ningning Li
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
- Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Sino-Danish Center for Education, Beijing 100049, People's Republic of China
| | - Junjun Wang
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Feng Wang
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
| | - Zhenxing Wang
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Jun He
- CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, People's Republic of China
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26
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Miao N, Sun Z. Computational design of two‐dimensional magnetic materials. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2021. [DOI: 10.1002/wcms.1545] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Naihua Miao
- School of Materials Science and Engineering Beihang University Beijing China
- Center for Integrated Computational Materials Engineering International Research Institute for Multidisciplinary Science, Beihang University Beijing China
| | - Zhimei Sun
- School of Materials Science and Engineering Beihang University Beijing China
- Center for Integrated Computational Materials Engineering International Research Institute for Multidisciplinary Science, Beihang University Beijing China
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27
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Och M, Martin MB, Dlubak B, Seneor P, Mattevi C. Synthesis of emerging 2D layered magnetic materials. NANOSCALE 2021; 13:2157-2180. [PMID: 33475647 DOI: 10.1039/d0nr07867k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
van der Waals atomically thin magnetic materials have been recently discovered. They have attracted enormous attention as they present unique magnetic properties, holding potential to tailor spin-based device properties and enable next generation data storage and communication devices. To fully understand the magnetism in two-dimensions, the synthesis of 2D materials over large areas with precise thickness control has to be accomplished. Here, we review the recent advancements in the synthesis of these materials spanning from metal halides, transition metal dichalcogenides, metal phosphosulphides, to ternary metal tellurides. We initially discuss the emerging device concepts based on magnetic van der Waals materials including what has been achieved with graphene. We then review the state of the art of the synthesis of these materials and we discuss the potential routes to achieve the synthesis of wafer-scale atomically thin magnetic materials. We discuss the synthetic achievements in relation to the structural characteristics of the materials and we scrutinise the physical properties of the precursors in relation to the synthesis conditions. We highlight the challenges related to the synthesis of 2D magnets and we provide a perspective for possible advancement of available synthesis methods to respond to the need for scalable production and high materials quality.
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Affiliation(s)
- Mauro Och
- Department of Materials, Imperial College London, SW72AZ London, UK.
| | - Marie-Blandine Martin
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
| | - Bruno Dlubak
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
| | - Pierre Seneor
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
| | - Cecilia Mattevi
- Department of Materials, Imperial College London, SW72AZ London, UK.
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28
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Yang S, Zhang T, Jiang C. van der Waals Magnets: Material Family, Detection and Modulation of Magnetism, and Perspective in Spintronics. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2002488. [PMID: 33511010 PMCID: PMC7816723 DOI: 10.1002/advs.202002488] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/09/2020] [Indexed: 06/02/2023]
Abstract
van der Waals (vdW) materials exhibit great potential in spintronics, arising from their excellent spin transportation, large spin-orbit coupling, and high-quality interfaces. The recent discovery of intrinsic vdW antiferromagnets and ferromagnets has laid the foundation for the construction of all-vdW spintronic devices, and enables the study of low-dimensional magnetism, which is of both technical and scientific significance. In this review, several representative families of vdW magnets are introduced, followed by a comprehensive summary of the methods utilized in reading out the magnetic states of vdW magnets. Thereafter, it is shown that various electrical, mechanical, and chemical approaches are employed to modulate the magnetism of vdW magnets. Finally, the perspective of vdW magnets in spintronics is discussed and an outlook of future development direction in this field is also proposed.
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Affiliation(s)
- Shengxue Yang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
| | - Tianle Zhang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
| | - Chengbao Jiang
- School of Materials Science and EngineeringBeihang UniversityBeijing100191P. R. China
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29
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Hu M, Xu S, Liu C, Zhao G, Yu J, Ren W. First-principles prediction of a room-temperature ferromagnetic and ferroelastic 2D multiferroic MnNX (X = F, Cl, Br, and I). NANOSCALE 2020; 12:24237-24243. [PMID: 33291136 DOI: 10.1039/d0nr06268e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two-dimensional (2D) multiferroic materials have great potential applications in multifunctional nanoelectronics devices. Here, we construct a series of stable and isolated monolayers as 2D manganese nitrohalides MnNX (X = F, Cl, Br, and I) and systematically investigate the structural, electronic and magnetic properties using first-principles and Monte Carlo simulations. We find that ground states simultaneously show in-plane ferroelasticity and room-temperature ferromagnetic properties. We also reveal that the in-plane magnetic anisotropy can be tunable by the uniaxial ferroelastic strain. Our results will provide significant implications for future experiments and the design of new functional materials at the nanoscale.
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Affiliation(s)
- Minglang Hu
- Physics Department, Shanghai Key Laboratory of High Temperature Superconductors, State Key Laboratory of Advanced Special Steel, International Centre of Quantum and Molecular Structures, Shanghai University, Shanghai 200444, China.
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30
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Miao N, Li W, Zhu L, Xu B, Zhou J, Elliott SR, Sun Z. Tunable phase transitions and high photovoltaic performance of two-dimensional In 2Ge 2Te 6 semiconductors. NANOSCALE HORIZONS 2020; 5:1566-1573. [PMID: 33073287 DOI: 10.1039/d0nh00395f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ultrathin semiconductors with great electrical and photovoltaic performance hold tremendous promise for fundamental research and applications in next-generation electronic devices. Here, we report new 2D direct-bandgap semiconductors, namely mono- and few-layer In2Ge2Te6, with a range of desired properties from ab initio simulations. We suggest that 2D In2Ge2Te6 samples should be highly stable and can be experimentally fabricated by mechanical exfoliation. They are predicted to exhibit extraordinary optical absorption and high photovoltaic conversion efficiency (≥31.8%), comparable to the most efficient single-junction GaAs solar cell. We reveal that, thanks to the presence of van Hove singularities in the band structure, unusual quantum-phase transitions could be induced in monolayers via electrostatic doping. Furthermore, taking bilayer In2Ge2Te6 as a prototypical system, we demonstrate the application of van der Waals pressure as a promising strategy to tune the electronic and stacking property of 2D crystals. Our work creates exciting opportunities to explore various quantum phases and atomic stacking, as well as potential applications of 2D In2Ge2Te6 in future nanoelectronics.
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Affiliation(s)
- Naihua Miao
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, China.
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31
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Coughlin AL, Xie D, Yao Y, Zhan X, Chen Q, Hewa-Walpitage H, Zhang X, Guo H, Zhou H, Lou J, Wang J, Li YS, Fertig HA, Zhang S. Near Degeneracy of Magnetic Phases in Two-Dimensional Chromium Telluride with Enhanced Perpendicular Magnetic Anisotropy. ACS NANO 2020; 14:15256-15266. [PMID: 33124799 DOI: 10.1021/acsnano.0c05534] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The discovery of atomically thin van der Waals magnets (e.g., CrI3 and Cr2Ge2Te6) has triggered a renaissance in the study of two-dimensional (2D) magnetism. Most of the 2D magnetic compounds discovered so far host only one single magnetic phase unless the system is at a phase boundary. In this work, we report the near degeneracy of magnetic phases in ultrathin chromium telluride (Cr2Te3) layers with strong perpendicular magnetic anisotropy highly desired for stabilizing 2D magnetic order. Single-crystalline Cr2Te3 nanoplates with a trigonal structure (space group P3̅1c) were grown by chemical vapor deposition. The bulk magnetization measurements suggest a ferromagnetic (FM) order with an enhanced perpendicular magnetic anisotropy, as evidenced by a coercive field as large as ∼14 kOe when the field is applied perpendicular to the basal plane of the thin nanoplates. Magneto-optical Kerr effect studies confirm the intrinsic ferromagnetism and characterize the magnetic ordering temperature of individual nanoplates. First-principles density functional theory calculations suggest the near degeneracy of magnetic orderings with a continuously varying canting from the c-axis FM due to their comparable energy scales, explaining the zero-field kink observed in the magnetic hysteresis loops. Our work highlights Cr2Te3 as a promising 2D Ising system to study magnetic phase coexistence and switches for ultracompact information storage and processing.
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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
| | - Yue Yao
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, United States
| | - Xun Zhan
- Electron Microscope Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Qiang Chen
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Heshan Hewa-Walpitage
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, United States
| | - Xiaohang Zhang
- Center for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, United States
| | - Hua Guo
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
| | - Haidong Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Jun Lou
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
| | - Jian Wang
- Department of Mechanical and Materials Engineering, University of Nebraska, Lincoln, Nebraska 68588, United States
| | - Yan S Li
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, 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
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
- Quantum Science and Engineering Center, Indiana University, Bloomington, Indiana 47405, United States
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32
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Zhong W, Zhao Y, Zhu B, Sha J, Walker ES, Bank S, Chen Y, Akinwande D, Tao L. Anisotropic thermoelectric effect and field-effect devices in epitaxial bismuthene on Si (111). NANOTECHNOLOGY 2020; 31:475202. [PMID: 32886647 DOI: 10.1088/1361-6528/abaf1f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This experimental study reveals intriguing thermoelectric effects and devices in epitaxial bismuthene, two-dimensional (2D) bismuth with thickness ⩽30 nm, on Si (111). Bismuthene exhibits interesting anisotropic Seebeck coefficients varying 2-5 times along different crystal orientations, implying the existence of a puckered atomic structure like black phosphorus. An absolute value of Seebeck coefficient up to 237 μV K-1 sets a record for elemental Bi ever measured to the best of our knowledge. Electrical conductivity of bismuthene can reach up to 4.6 × 104 S m-1, which is sensitive to thickness and magnetic field. Along with a desired low thermal conductivity ∼1.97 W m-1 K that is 20% of its bulk form, the first experimental zT value at room temperature for bismuthene was measured ∼10-2, which is much higher than many other VA Xenes and comparable to its bulk compounds. Above results suggest a mixed buckled and puckered Bi atomic structure for epitaxial 2D bismuth on Si (111). Our work paves the way to explore potential applications, such as heat flux sensor, energy converting devices and so on for bismuthene.
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Affiliation(s)
- Wen Zhong
- School of Materials Science and Engineering, Jiangsu Key Laboratory of Advanced Metallic Materials, Southeast University, Nanjing 211189, People's Republic of China
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33
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Chen S, Wu F, Li Q, Sun H, Ding J, Huang C, Kan E. Prediction of room-temperature ferromagnetism in a two-dimensional direct band gap semiconductor. NANOSCALE 2020; 12:15670-15676. [PMID: 32677637 DOI: 10.1039/d0nr03340e] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Two-dimensional (2D) ferromagnetic (FM) semiconductors with a direct electronic band gap have recently drawn much attention due to their promising potential for spintronic and magneto-optical applications. However, the Curie temperature (TC) of recently synthesized 2D FM semiconductors is too low (∼45 K) and a room-temperature 2D direct band gap FM semiconductor has never been reported, which hinders the development for practical magneto-optical applications. Here, we show that through isovalent alloying, one can increase the TC of a 2D FM semiconductor up to room temperature and simultaneously turn it from an indirect to a direct band gap semiconductor. Using the first-principles calculations, we predict that the alloyed CrMoS2Br2 monolayer is a direct band gap semiconductor with a TC of ∼360 K, whereas the pristine CrSBr monolayer is an indirect band gap semiconductor with a TC of ∼180 K. These findings provide a promising pathway to realize 2D direct band gap FM semiconductors with TC above room temperature, which will greatly stimulate theoretical and experimental interest in future spintronic and magneto-optical applications.
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Affiliation(s)
- Shanbao Chen
- Department of Applied Physics and Institution of Energy and Microstructure, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, P. R. China.
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34
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Nair AK, Rani S, Kamalakar MV, Ray SJ. Bi-stimuli assisted engineering and control of magnetic phase in monolayer CrOCl. Phys Chem Chem Phys 2020; 22:12806-12813. [PMID: 32469019 DOI: 10.1039/d0cp01204a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Magnetic phase control and room temperature magnetic stability in two-dimensional (2D) materials are indispensable for realising advanced spintronic and magneto-electronic functions. Our current work employs first-principles calculations to comprehensively study the magnetic behaviour of 2D CrOCl, uncovering the impact of strain and electric field on the material. Our studies have revealed that uniaxial strain leads to the feasibility of room temperature ferromagnetism in the layer and also detected the occurrence of a ferromagnetic → antiferromagnetic phase transition in the system, which is anisotropic along the armchair and zigzag directions. Beyond such a strain effect, the coupling of strain and electric field leads to a remarkable enhancement of the Curie temperature (Tc) ∼ 450 K in CrOCl. These predictions based on our detailed simulations show the prospect of multi-stimuli magnetic phase control, which could have great significance for realizing magneto-mechanical sensors.
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Affiliation(s)
- A K Nair
- Department of Physics, Indian Institute of Technology Patna, Bihta 801106, India.
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