The optical properties of the layered magnet CrSBr are dominated by intralayer excitons: the antiferromagnetic order between the layers makes layer-to-layer charge hopping, and therefore interlayer excitons, spin-forbidden. An external magnetic field, however, continuously drives the magnetic order towards layer-to-layer ferromagnetic, which opens spin-allowed charge-transfer channels between the layers. Here we elaborate how their admixture changes the composition and nature of the excitons, leading to an extension over many layers, and causes a quadratic red-shift with respect to the external magnetic field. We address these effects by ab-initio $GW$-BSE calculations as a function of magnetic field and cast the data into a minimal four-band model to elucidate the interplay between the various interaction and coupling mechanisms. Our findings should be generally valid for antiferromagnetic layered magnets with and without external magnetic fields, and moreover for any couple of layers with different spin directions. Our insights help to systematically address excitons and predict their optical signatures in such systems.
Electric-field-driven magnetic switching and tightly bound interlayer excitons in bilayer CrSBr
Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology（华中科技大学物理学院）；School of Physics and Technology, Wuhan University（武汉大学物理科学与技术学院）；National Institute for Material Science（日本国立材料研究所）
Spin waves in the bilayer van der Waals magnet CrSBr
Delft University of Technology（代尔夫特理工大学）；V.G. Baryakhtar Institute of Magnetism of the NAS of Ukraine（乌克兰国家科学院V.G.巴里亚赫塔尔磁学研究所）；Institute of Spintronics and Quantum Information, Faculty of Physics and Astronomy, Adam Mickiewicz University（亚当·密茨凯维奇大学物理与天文学学院自旋电子学与量子信息研究所）；WPI-AIMR & IMR & CSIS, Tohoku University（东北大学WPI-先进物质与器件研究所(IMR)及材料系统国际研究前沿中心(CSIS)）；Kavli Institute for Theoretical Sciences, University of the Chinese Academy of Sciences（中国科学院大学卡弗里理论科学研究所）
Layer- and Field-Dependent Magnetic Order in 2D CrSBr Revealed by Pulsed Nanocalorimetry
Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST（加泰罗尼亚纳米科学和纳米技术研究所）；Universitat Autònoma de Barcelona（巴塞罗那自治大学）；Université Catholique de Louvain (UCLouvain)（天主教鲁汶大学）；Institut de Microelectrònica de Barcelona (IMB-CNM-CSIC)（巴塞罗那微电子研究所）；Columbia University（哥伦比亚大学）；WEL Research Institute（WEL研究所）；National Institute for Materials Science（日本国立材料研究所）
Layer-Dependent Phonons, Excitons, and Magneto-Optical Phenomena in CrSBr: A Mini Review
National Center for Nanoscience and Technology（中国科学院国家纳米科学中心）；University of Chinese Academy of Sciences（中国科学院大学）；University of Warsaw（华沙大学）；CNRS–UGA–UPS–INSA–EMFL（法国国家科学研究中心-格勒诺布尔阿尔卑斯大学-图卢兹第三大学-INSA图卢兹-东洛林大学）；University of Sapienza（罗马第一大学）
Magnetic Order and Symmetry in the 2D Semiconductor CrSBr
最近发现的二维（2D）磁铁提供了独特的机会，为实验探索低维磁学4和磁邻近效应，并为新的磁电，磁光和自旋电子器件的发展。这些进展需要具有不同磁性结构的2D材料以及有效的磁对称性探针，这是理解层内磁序和层间磁耦合的关键。在这里，我们应用二次谐波产生（SHG），一种对对称性破缺非常敏感的技术，来探测一种新的二维磁性半导体CrSBr的磁性结构。我们发现，CrSBr单层铁磁有序低于146 K，一个巨大的磁偶极子SHG效应的中心对称的2D结构的发现，使观察。在多层膜中，铁磁单层膜是反铁磁耦合的，Néel温度随着层数的减少而显著增加。CrSBr的磁结构包括与矩形晶胞共面对准的自旋，与具有面外力矩的原型2D六边形磁体CrI 3和Cr2 Ge 2 Te 6显著不同。此外，我们的二次谐波分析表明，铁磁单层和反铁磁双层的序参量分别是磁偶极子和磁环矩。这些发现确立了CrSBr作为一种令人兴奋的2D磁性半导体和SHG作为探测2D磁对称性的有力工具，为探索磁序和激子/电子性质之间的耦合以及磁环矩在广泛的应用中打开了大门。
Switchable Exchange Bias Resulting from Correlated Domain Structures in Orthogonally Coupled Antiferromagnet/Ferromagnet van der Waals Heterostructures
Layer-selective detection of magnetization directions from two layers of antiferromagnetically-coupled magnetizations by ferromagnetic resonance using a spin-torque oscillator
Interlayer Coupling and Floquet-Driven Topological Phases in Bilayer Haldane Lattices
Zhejiang Normal University（浙江师范大学）；Khazar University（哈扎尔大学）；Quaid-I Azam University Islamabad（巴基斯坦奎德-阿扎姆大学伊斯兰堡分校）；Institute for Research in Fundamental Sciences (IPM)（伊朗基础科学研究院）
Enhancement of the WS$_2$ A$_{1\text{g}}$ Raman Mode in MoS$_2$/WS$_2$ Heterostructures
Institute of Physics, Rostock University（罗斯托克大学物理研究所）；Institute of Theoretical Physics, University of Warsaw（华沙大学理论物理研究所）；Institute of Theoretical Physics, Wrocław University of Science and Technology（弗罗茨瓦夫科技大学理论物理研究所）；Department of Physics, Freie Universität Berlin（柏林自由大学物理系）；Institute of Physical Chemistry, Friedrich Schiller University Jena（耶拿弗里德里希·席勒大学物理化学研究所）；Department of Physics and Materials Science, University of Luxembourg（卢森堡大学物理与材料科学系）
Layer-Number-Controlled Symmetry Breaking and Surface-State Transport in Rhombohedral Graphene Multilayers
State Key Laboratory of Micro-nano Engineering Science, Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Tsung-Dao Lee Institute and School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院）；Department of Quantum Matter Physics, University of Geneva（日内瓦大学量子物质物理系）；Department of Physics, University of Seoul（首尔大学物理系）；Research Center for Electronic and Optical Materials, National Institute for Materials Science（国家材料科学研究所电子光学材料研究中心）；Research Center for Materials Nanoarchitectonics, National Institute for Materials Science（国家材料科学研究所材料纳米架构研究中心）；Department of Smart Cities, University of Seoul（首尔大学智慧城市系）
Electrode-tunable nonlocal charge to spin conversion in WSe$_2$-intercalated bilayer graphene
Institute of Informatics, Slovak Academy of Sciences（斯洛伐克科学院信息学研究所）；Faculty of Physics, University of Belgrade（贝尔格莱德大学物理学院）；Institute of Physics, Pavol Jozef Šafárik University in Košice（科希策帕维尔·约瑟夫·沙法里克大学物理研究所）；Institute of Experimental Physics, Slovak Academy of Sciences（斯洛伐克科学院实验物理研究所）；New Technologies Research Centre, University of West Bohemia（西波希米亚大学新技术研究中心）
