Evolution of magnetic order in van-der-Waals antiferromagnet FePS$_3$ through insulator-metal transition
Matthew J. Coak, David M Jarvis, Hayrullo Hamidov, Andrew R. Wildes, Joseph A. M. Paddison, Cheng Liu, Charles R. S. Haines, Ngoc T. Dang, Sergey E. Kichanov, B… 展开作者
Matthew J. Coak, David M Jarvis, Hayrullo Hamidov, Andrew R. Wildes, Joseph A. M. Paddison, Cheng Liu, Charles R. S. Haines, Ngoc T. Dang, Sergey E. Kichanov, Boris N. Savenko, Sungmin Lee, Marie Kratochvílová, Stefan Klotz, Thomas Hansen, Denis P. Kozlenko, Je-Geun Park, Siddharth S. Saxena
Layered van-der-Waals 2D magnetic materials are of great interest in fundamental condensed-matter physics research, as well as for potential applications in spintronics and device physics. We present neutron powder diffraction data using new ultra-high-pressure techniques to measure the magnetic structure of Mott-insulating 2D honeycomb antiferromagnet FePS$_3$ at pressures up to 183 kbar and temperatures down to 80 K. These data are complemented by high-pressure magnetometry and reverse Monte Carlo modeling of the spin configurations. As pressure is applied, the previously-measured ambient-pressure magnetic order switches from an antiferromagnetic to a ferromagnetic interplanar interaction, and from 2D-like to 3D-like character. The overall antiferromagnetic structure within the $ab$ planes, ferromagnetic chains antiferromagnetically coupled, is preserved, but the magnetic propagation vector is altered from $(0\:1\:\frac{1}{2})$ to $(0\:1\:0)$, a halving of the magnetic unit cell size. At higher pressures, coincident with the second structural transition and the insulator-metal transition in this compound, we observe a suppression of this long-range-order and emergence of a form of magnetic short-range order which survives above room temperature. Reverse Monte Carlo fitting suggests this phase to be a short-ranged version of the original ambient pressure structure - with a return to antiferromagnetic interplanar correlations. The persistence of magnetism well into the HP-II metallic state is an observation in seeming contradiction with previous x-ray spectroscopy results which suggest a spin-crossover transition.
Emergent Polar Metal Phase in a Van der Waals Mott Magnet
University of Cambridge（剑桥大学）；Institut Laue-Langevin（朗之万研究所）；University of Birmingham（伯明翰大学）；University of East Anglia（东英吉利大学）；Navoi State University of Mining and Technologies（纳沃伊国立矿业与技术大学）；Diamond Light Source（钻石光源）
The influence of spin-phonon coupling on antiferromagnetic spin fluctuations in FeSe under pressure: the First-principles calculations with van der Waals corrections
Kitaev interactions in the van der Waals antiferromagnet VBr3
Fudan University（复旦大学）；J-PARC Center（日本原子力研究开发机构J-PARC中心）；Shanghai Research Center for Quantum Sciences（上海量子科学研究中心）；Institute of Nanoelectronics and Quantum Computing, Fudan University（复旦大学纳米电子与量子计算研究所）
研究通过非弹性中子散射揭示了van der Waals反铁磁体VBr3中的Kitaev相互作用，并表明配体工程可调节Kitaev相互作用。
A van der Waals antiferromagnetic topological insulator with weak interlayer magnetic coupling
磁性拓扑绝缘体（TI）是研究量子反常霍尔效应（QAH）和马约拉纳模（Majorana模）等量子现象的重要材料平台，其成功的材料实现对我们的基本认识和潜在的技术革命至关重要。通过实现具有交替的七层[MnBi 2 Te 4]和五层[Bi 2 Te 3]层的体材料MnBi 4 Te 7，我们表明它在平面内是铁磁的，但沿c轴是反铁磁的，在2 K时的面外饱和场为~ 0.22 T.我们的角分辨光电子能谱测量和第一性原理计算进一步证明了MnBi 4 Te 7是一个Z2反铁磁TI与两种类型的表面状态与[MnBi 2 Te 4]或[Bi 2 Te 3]终止，分别。此外，其超晶格性质可以通过剥离使[MnBi 2 Te 4]和[Bi 2 Te 3]层的各种异质结构成为可能。因此，MnBi_4Te_7的低饱和场和超晶格性质使其成为研究丰富涌现现象的理想体系。
Low-energy excitations and magnetic anisotropy of the layered van der Waals antiferromagnet Ni$_2$P$_2$S$_6$
准二维反铁磁体Ni $_2$ P $_2$ S $_6$属于磁性范德华化合物家族，为实现低维量子磁性的基本模型提供了丰富的物质基础。在这里，我们报告高频/高磁场电子自旋共振测量单晶镍$_2$ P $_2$ S $_6$。结果使人们能够可靠地确定积极的，“容易”平面类型的单离子各向异性的Ni $^{2+}$离子的上限，其幅度$\lesssim 0.7$毫电子伏。共振响应揭示了强烈的各向异性自旋波动设置在略高于Néel温度$T_{\rm N} = 158$ K，并在反铁磁有序状态下延伸到低温。在那里，一个低能的磁振子激发间隙从基态只有$\sim 1$ meV被发现。这种磁振子模式可以解释不寻常的低温弛豫过程中所观察到的最新的核磁共振实验，并与单离子各向异性的估计，他们应该能够建立一个现实的自旋模型，准确描述的磁性Ni $_2$ P $_2$ S $_6$。
Kondo-coupled van der Waals antiferromagnet with high-mobility quasiparticles
Wuhan National High Magnetic Field Center（武汉国家强磁场中心）；School of Physics, Huazhong University of Science and Technology（华中科技大学物理学院）；School of Physics, Nanjing University（南京大学物理学院）；Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences（中国科学院合肥物质科学研究院强磁场实验室、安徽低能量子材料与器件重点实验室）；School of Physics and Electronics, Henan University（河南大学物理与电子学院）；State Key Laboratory of Advanced Electromagnetic Technology, Huazhong University of Science and Technology（华中科技大学先进电磁技术国家重点实验室）
Revealing the Electronic Structure of van der Waals Antiferromagnetic NiPS$_3$ through Synchrotron-Based $μ$-ARPES and Alkali Metal Dosing
Boston University（波士顿大学）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Rice University（莱斯大学）；Universidade Federal de Ouro Preto（欧罗普雷托联邦大学）；Universidade Federal de Minas Gerais（米纳斯吉拉斯联邦大学）；University of Bristol（布里斯托大学）
Field-rigid Ising antiferromagnetism with giant spin-flip fields in Van der Waals UOTe
Washington University in St. Louis（圣路易斯华盛顿大学）；National High Magnetic Field Laboratory, Los Alamos National Laboratory（洛斯阿拉莫斯国家实验室国家高磁场实验室）；Neutron Scattering Division, Oak Ridge National Laboratory（橡树岭国家实验室中子散射部）；Harvard University（哈佛大学）；National High Magnetic Field Laboratory, Florida State University（佛罗里达州立大学国家高磁场实验室）
Magnetic Field-Tunable Repulsive Exciton-Exciton Interaction in the van der Waals Antiferromagnet NiPS$_3$
The Institute for Solid State Physics, The University of Tokyo（东京大学固体研究所）；Department of Physics and Astronomy, Seoul National University (SNU)（首尔大学物理天文学系）
