Rahul S, Sarkar Sujit
Department of Theoretical Sciences, Poornaprajna Institute of Scientific Research, 4, Sadashivanagar, Bangalore, 560080, India.
Department of Theoretical Sciences, Poornaprajna Institute of Scientific Research, Bidalur Post, Devanhalli, Bangalore Rural, 562110, India.
Sci Rep. 2022 Apr 28;12(1):6993. doi: 10.1038/s41598-022-11126-7.
An attempt is made to study the quantum criticality in non-Hermitian system with topological characterization. We use the zero mode solutions to characterize the topological phases and, criticality and also to construct the phase diagram. The Hermitian counterpart of the model Hamiltonian possess quite a few interesting features such as Majorana zero modes (MZMs) at criticality, unique topological phase transition on the critical line and hence these unique features are of an interest to study in the non-Hermitian case also. We observe a unique behavior of critical lines in presence of non-Hermiticity. We study the topological phase transitions in the non-Hermitian case using parametric curves which also reveal the gap closing point through exceptional points. We study bulk and edge properties of the system where at the edge, the stability dependence behavior of MZMs at criticality is studied and at the bulk we study the effect of non-Hermiticity on the topological phases by investigating the behavior of the critical lines. The study of non-Hermiticity on the critical lines revels the rate of receding of the topological phases with respect to the increase in the value of non-Hermiticity. This work gives a new perspective on topological quantum criticality in non-Hermitian quantum system.
我们尝试研究具有拓扑特征的非厄米系统中的量子临界性。我们使用零模解来表征拓扑相和临界性，并构建相图。模型哈密顿量的厄米对应物具有许多有趣的特征，例如临界时的马约拉纳零模（MZMs）、临界线上独特的拓扑相变，因此这些独特特征在非厄米情况下也值得研究。我们观察到在存在非厄米性时临界线的独特行为。我们使用参数曲线研究非厄米情况下的拓扑相变，这些曲线也通过例外点揭示能隙闭合点。我们研究系统的体和边缘性质，在边缘处研究临界时MZMs的稳定性依赖行为，在体中通过研究临界线的行为来研究非厄米性对拓扑相的影响。对临界线上非厄米性的研究揭示了拓扑相相对于非厄米性值增加的后退速率。这项工作为非厄米量子系统中的拓扑量子临界性提供了新的视角。
