层状手性拓扑磁材料Cr1/3NbS2的磁学特性

伴随着拓扑材料的出现,拓扑物理学成为了当代凝聚态物理的前沿与热点之一.拓扑特性是描述材料的物理量在连续变换下会保持不变的性质(如陈数Chern number),种类包括拓扑绝缘体、外尔和狄拉克等拓扑半金属、拓扑磁材料等.一维手性磁孤子(chiral magnetic solitons),类似于磁性斯格明子(skyrmions),是一类具有拓扑性和准粒子性的磁结构,具有丰富的物理特性和潜在应用价值.本文详细总结了一种具有一维手性磁孤子结构的晶体Cr1/3NbS2,包括其晶体构型、磁相互作用、磁结构、维度调控以及相变物理等物理特性.希望本综述能为研究拓扑磁材料的科研人员提供详实的参考,为将拓扑和手性磁性引入到二维层状材料家族提供研究思路,促进拓扑磁电子学的发展,为相关器件提供更多的材料选择和理论基础.

Magnetic properties of layered chiral topological magnetic material Cr1/3NbS2

With the discovery and development of topological materials,topological physics has attracted enormous research interest in the fields of contemporary condensed matter physics.Topological property,which describes such a property that physical quantity remains invariant under continuous transformation(such as Chern number),has been revealed in a variety of materials,including topological insulators,topological semimetals(such as Weyl or Dirac semimetals),topological magnetic materials,etc.One-dimensional chiral magnetic soliton,similar to magnetic skyrmion,is a type of magnetic configuration with topological origin and quasiparticle property,which has shown tremendous physical properties and device functionalities.In this review,we mainly focus on a chiral helimagnet,called Cr1/3NbS2,which possesses chiral magnetic soliton lattice and other more spin configurations under different conditions.We systematically summarize the work on Cr1/3NbS2,discussing its crystal symmetry,band structure,magnetic interactions,rich magnetic phases,and the physics of associated phase transitions.In particular,the layered crystal structure of Cr1/3NbS2 enables us to control the soliton number through tuning the layer number or crystal thickness.Our review provides a comprehensive summary of Cr1/3NbS2 in order to draw more attention to this interesting material.Moreover,we envision that our work could offer useful guidance to the researchers working on topological and chiral magnetic materials,and thus introducing topological or chiral magnetism into two-dimensional layered materials and promoting the development of modern magnetism and spintronics.Therefore,this review mainly focuses on a magnet,called Cr1/3NbS2.We systematically summarize the work on Cr1/3NbS2,discussing its crystal symmetry,band structure,magnetic interaction,rich magnetic phases and the interesting physical phenomena occurring at each phase transition.In addition,the layered crystal structure of Cr1/3NbS2 also enables us to use the layer number or crystal thickness to modulate and control its rich magnetic phases.We believe that our review provides a comprehensive summary of Cr1/3NbS2,which can make people have a better understanding of a typical topological magnetic material,thereby enriching the material types of magnets and low-dimensional material family and promoting the development of magnetism and spintronics applications,such as in magnetic memory devices,spintronic devices,and quantum information devices.