Valley modulation and topological phase transition in staggered kagome ferromagnets  

作　　者：Yuheng Xing Wenjuan Qiu Xinxing Wu Yue Tan 邢玉恒;邱文娟;吴新星;谭悦(Department of Physics,School of Mathematics and Physics,Yancheng Institute of Technology,Yancheng 224051,China)

机构地区：[1]Department of Physics,School of Mathematics and Physics,Yancheng Institute of Technology,Yancheng 224051,China

出　　处：《Chinese Physics B》2024年第12期416-421,共6页中国物理B（英文版）

基　　金：support from the Funding for School-level Research Projects of Yancheng Institute of Technology(Grant Nos.xjr2020038,xjr2022039,and xjr2022040)。

摘　　要：Owing to their charge-free property,magnons are highly promising for achieving dissipationless transport without Joule heating,and are thus potentially applicable to energy-efficient devices.Here,we investigate valley magnons and associated valley modulations in a kagome ferromagnetic lattice with staggered exchange interaction and Dzyaloshinskii-Moriya interaction.The staggered exchange interaction breaks the spatial inversion symmetry,leading to a valley magnon Hall effect.With nonzero Dzyaloshinskii-Moriya interaction in a staggered kagome lattice,the magnon Hall effect can be observed from only one valley.Moreover,reversing the Dzyaloshinskii-Moriya interaction(D→-D)and exchanging J_(1)and J_(2)(J_(1)■J_(2))can also regulate the position of the unequal valleys.With increasing Dzyaloshinskii-Moriya interaction,a series of topological phase transitions appear when two bands come to touch and split at the valleys.The valley Hall effect and topological phase transitions observed in kagome magnon lattices can be realized in thin films of insulating ferromagnets such as Lu_(2)V_(2)O_(7),and will extend the basis for magnonics applications in the future.

关 键 词：valley modulation Dzyaloshinskii-Moriya interaction staggered kagome ferromagnets topological phase transitions magnon Hall effect 

分 类 号：O469[理学—凝聚态物理]