Non-Hermitian disorder-driven topological transition in a dimerized Kitaev superconductor chain

Abstract

Recently, topological phases in non-Hermitian systems have attracted great attention. In most of these works, disorders are added to the chemical potential or hopping term and the topological transition driven by disordered loss and gain has not been found. In this paper, we investigate the one-dimensional dimerized Kitaev superconductor chain with balanced loss and gain. In the clean limit, the phase diagram is given by calculating the Bloch winding number and real-space energy spectrum. Furthermore, by calculating the disorder-averaged real-space winding number and disorder-averaged real-space energy spectrum, we identify a topological transition driven by the disordered balanced loss and gain. The disorder-averaged inverse participate ratio of each eigenstate, mean inverse participate ratio, and density distribution of the edge mode are also calculated to support the existence of the topological Anderson phase. Finally, we compare our model with the Hermitian disordered Kitaev chain and discuss the possible experimental scheme of our model. Our work offers a minimal start point to explore the interplay between the dissipation and Majorana zero modes in the topological superconductor.