无序非厄米Su-Schrieffer-Heeger中的趋肤效应  

Skin effect in disordered non-Hermitian Su-Schrieffer-Heeger

作　　者：刘佳琳 庞婷方 杨孝森 王正岭[1] Liu Jia-Lin;Pang Ting-Fang;Yang Xiao-Sen;Wang Zheng-Ling(Department of Physics,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学物理与电子工程学院,镇江212013

出　　处：《物理学报》2022年第22期299-305,共7页Acta Physica Sinica

摘　　要：近年来,非厄米系统涌现出了大量新颖现象,比如传统体边对应的失效、非厄米趋肤效应(non-Hermitian skin effect)等等.本文通过逆参与率和平均逆参与率,研究非厄米Su-Schrieffer-Heeger (SSH)模型的本征态的局域性以及非厄米趋肤效应,并且研究了系统的体边对应率.在此基础上,进一步研究了同位无序对系统非厄米趋肤效应的影响.发现,由于受到拓扑保护,无序不会破坏拓扑零能的波函数局域性,但是会极大地影响体态的非厄米趋肤效应.引入无序以后,系统的体态将会迅速扩展到体内.非厄米趋肤效应对同位无序表现了脆弱性.当无序增强,非厄米趋肤效应会受到很大的压制.无序会减小系统的能隙和虚部能量.我们的研究加深了人们对非厄米趋肤效应的认识.In recent years, a large number of novel phenomena such as the breakdown of conventional bulk-boundary correspondence and non-Hermitian skin effect, have emerged in non-Hermitian systems. In this work, we investigate the localization of the eigenstates and the non-Hermitian skin effect of the disordered non-Hermitian Su-Schrieffer-Heeger(SSH) model by inverse participation rate(IPR) and average inverse participation rate(MIPR). We also investigate the bulk-boundary correspondence ratio of the system. Based on the above, we further investigate the effect of disorder on the non-Hermitian skin effect and the topological properties of the NH system. We find that the disorder does not destroy the localization of the topological edge state due to the protection from the topology of the system. But the eigenstates of bulk are greatly affected by the disorder. In the presence of disorder, the eigenstates of the bulk will rapidly extend into the bulk. Thus, the non-Hermitian skin effect is vulnerable to the disorder. When the disorder is enhanced, the non-Hermitian skin effect will be greatly suppressed. We also show that the disorder will reduce the energy gap and imaginary energy of the system. Our study contributes to the further understanding of the non-Hermitian skin effect.

关 键 词：非厄米趋肤效应 无序 逆参与率 

分 类 号：O413.1[理学—理论物理]