The size effect and analogous boundary states in a circular non-Hermitian chain  

作　　者：Xin-Yu Ma Yi-Han Guan Qiao-Nan Li Ai-Lei He Lu Qi 

机构地区：[1]School of Physical Science and Technology,Yangzhou University,Yangzhou 225002,China

出　　处：《Communications in Theoretical Physics》2024年第2期157-165,共9页理论物理通讯（英文版）

基　　金：supported by the National Natural Science Foundation of China under Grants No.12304557,No.12204404。

摘　　要：We investigate the size effect and boundary states based on a circular non-Hermitian chain under the nonreciprocal intra-cell coupling and inter-cell coupling regimes.We find that the circular non-Hermitian chain exhibits an even–odd effect on the unit cell corresponding to a large chain,which is different from the open non-Hermitian chain only exhibiting the same effect for a small chain.Moreover,we find that the originally localized bulk states become totally extended via designing the boundary coupling strength appropriately.The extended bulk states reveal the fact of the disappearance of the non-Hermitian skin effect.In particular,we show that the circular non-Hermitian chain also possesses the analogous edge states under some parameter regimes,which is pretty counterintuitive since the circular chain usually cannot define a boundary.Our investigations supply the different non-Hermitian phenomena in a circular non-Hermitian chain.

关 键 词：boundary states non-Hermitian chain topological state 

分 类 号：O469[理学—凝聚态物理]