Ligand Mediated Magnetic Coupling Across Metamagnetic Transitions in CrPS4
European Synchrotron Radiation Facility（欧洲同步辐射装置）；Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL（格勒诺布尔阿尔卑斯大学、法国国家科学研究中心、格勒诺布尔理工学院、NEEL研究所）；Dipartimento di Fisica, Politecnico di Milano（米兰理工大学物理系）
Giuseppe Buccoliero, Rachel Nickel, Roberto Sant, Marli dos Reis Cantarino, Andrei Rogalev, Nathan J. Yutronkie, Tristan Riccardi, Daniel A. Chaney, Kurt Kummer… 展开作者
Giuseppe Buccoliero, Rachel Nickel, Roberto Sant, Marli dos Reis Cantarino, Andrei Rogalev, Nathan J. Yutronkie, Tristan Riccardi, Daniel A. Chaney, Kurt Kummer, Johann Coraux, Nicholas B. Brookes
Chromium thiophosphate (CrPS4) is a long-known material: a layered semiconducting antiferromagnet. Its recently discovered gate-tunable metamagnetic phase transitions, the remarkable positive and oscillating magnetoresistance as a tunnel barrier, and its Fano-resonance luminescence, elusive among the multitude of Cr3+ compounds, call for revisiting the understanding of its electronic structure, especially regarding how it relates to magnetic order. Here, we employ X-ray magnetic circular dichroism, implemented in both absorption and resonant inelastic X-ray spectroscopies, together with quantum many-body calculations, to unveil the role of metal-ligand covalency in mediating the metamagnetic transitions in CrPS4, using crystal-field and charge-transfer excitations as fingerprints of the evolving magnetic order. We reveal the role of extended superexchange paths involving P and S atoms, coupling interactions between the Cr spins across the different magnetic phases: antiferromagnetic, canted, and ferromagnetic. Our results elucidate the electronic states involved in these phases and provide prescriptions for engineering the metamagnetic phase diagram of CrPS4.
Polaron-mediated metal-insulator transition and proton conduction in hydrogenated nickelate perovskites
School of Physics and Astronomy, Beijing Normal University（北京师范大学物理学院）；Key Laboratory of Multiscale Spin Physics (Beijing Normal University), Ministry of Education（教育部多尺度自旋物理重点实验室（北京师范大学））；College of Physics, Hebei Normal University（河北师范大学物理学院）；Hebei Advanced Thin Films Laboratory（河北省先进薄膜实验室）
Sb-5$p$-mediated antiparallel Nd-Fe coupling in Nd$_3$Fe$_3$Sb$_7$
Helmholtz-Zentrum Dresden-Rossendorf（德累斯顿罗森多夫亥姆霍兹中心）；Würzburg-Dresden Cluster of Excellence ctd.qmat（维尔茨堡-德累斯顿卓越集群ctd.qmat）；Technische Universität Dresden（德累斯顿工业大学）；Leibniz IFW Dresden（德累斯顿莱布尼茨固体与材料研究所）；Birla Institute of Technology Mesra（米斯拉比尔拉理工学院）；Faculty of Chemistry and Food Chemistry（化学与食品化学学院）；UGC-DAE Consortium for Scientific Research Mumbai Centre（UGC-DAE科学研究联盟孟买中心）
Non-magnetic and magnetic thiolate-protected Au25 superatoms on Cu(111), Ag(111) and Au(111) surfaces
用自旋极化密度泛函理论研究了巯基甲烷稳定的Au $_{25}$ L $_{18}$和MnAu $_{24}$ L $_{18}$（L = SCH $_3$）团簇在贵金属（111）表面的几何结构、电子结构和磁性.簇和表面之间的相互作用被发现是介导的电荷转移主要从或进入配体单层。13原子金属核的电子性质在所有情况下保持不变，而在气相中的孤立的集群相比。取决于表面，Au $_{25}$ L $_{18}$簇保留在0.7 eV至1.0 eV范围内的清晰HOMO-LUMO能隙.配体层能够使磁性MnAu $_{24}$ L $_{18}$团簇的电子结构与Au（111）表面解耦，保留由自旋极化Mn（3d）电子产生的接近5 $μ_{B}$的高局部自旋矩。这些计算意味着硫醇单层保护的金团簇可以用作具有可调能隙、隧穿势垒和磁矩的有前途的构建块，用于电子和/或自旋输运领域。
Structural, electronic, and magnetic properties of tris(8-hydroxyquinoline)iron(III) molecules and its magnetic coupling with ferromagnetic surface: first-principles study
Photoemission and X-ray Absorption Studies of the Diluted Magnetic Semiconductor Ba$_{1-y}$K$_{y}$(Zn$_{1-x}$Mn$_{x}$)$_{2}$As$_{2}$ Isostructural to Fe-based Superconductors
用X射线吸收谱和共振光电子能谱研究了一种与铁基超导体122型同构的新型稀磁半导体（DMS）Ba $_{1-x}$ K $_{x}$（Zn $_{1-y}$ Mn $_{y}$）$_{2}$ As $_{2}$的电子和磁性. Mn $L_{2,3}$ -边XAS表明掺杂的Mn原子具有2+的价态，并且与四面体配位的As配体的$4p$轨道强烈杂化。通过RPES获得的Mn $3d$部分态密度（PDOS）显示出在4 eV附近的峰，并且在费米能级（$E_{F}$）以下0-2 eV之间相对较高，在$E_{F}$处几乎没有贡献，类似于原型DMS Ga $_{1-x}$ Mn $_{x}$ As。该能级在Mn原子处产生具有$S=5/2$局部磁矩的$d^{5}$电子构型。由K取代Ba原子诱导的空穴载流子进入As $4p$价带的顶部，并与Mn局域自旋弱结合。在Ba $_{1-x}$ K $_{x}$（Zn $_{1-y}$ Mn $_{y}$）$_{2}$ As $_{2}$中，由空穴载流子介导的局域自旋之间的铁磁关联诱导铁磁性
Ubiquitous impact of localised impurity states on the exchange coupling mechanism in magnetic topological insulators
自从在磁性掺杂拓扑绝缘体（MTI）Cr：（Bi，Sb）$_2$ Te $_3$和V：（Bi，Sb）$_2$ Te $_3$中发现量子反常霍尔效应以来，寻找铁磁性发生的交换耦合机制一直是一个中心问题，并提出了各种不同的方案。结合共振光电子能谱、X射线磁二向色性和多重配位场论，我们确定了（Bi，Sb）$_2$ Te $_3$中V和Cr杂质的局域电子和磁性组态。虽然强的pd杂化被发现这两种掺杂剂类型，其三维态密度显示出显着的差异。最先进的第一性原理计算显示了这些杂质状态如何介导特征短程pd交换相互作用，其强度敏感地随3d状态相对于费米能级的位置而变化。不同的主机化学计量的薄膜上的测量支持这一趋势。我们的研究结果建立了必不可少的作用，杂质状态介导的交换相互作用的磁性MTI。
Field-induced magnetic phase transitions and transport anomalies in GdAlSi
Zhejiang University（浙江大学）；Zhejiang University of Technology（浙江工业大学）；Anhui University（安徽大学）；Institute of Physical Science and Information Technology, Anhui University（安徽大学物理科学与信息技术研究院）；State Key Laboratory of Silicon and Advanced Semiconductor Materials, Zhejiang University（浙江大学硅材料与先进半导体技术国家重点实验室）；Hefei National Laboratory（合肥国家实验室）
