Non-Hermiticity enhanced topological immunity of one-dimensional $p$-wave superconducting chain

TL;DR

This paper shows that non-Hermiticity can strengthen the robustness of topological edge states, specifically Majorana zero modes, in a one-dimensional p-wave superconducting chain against non-local disorder, revealing new interplay between non-Hermiticity and topology.

Contribution

It introduces a generalized 1D Kitaev model with asymmetric hopping demonstrating enhanced topological immunity due to non-Hermiticity, supported by numerical and analytical analysis.

Findings

Non-Hermiticity enlarges the region supporting Majorana zero modes.

Non-Hermiticity stabilizes the topological phase against higher disorder.

Enhanced robustness of topological superconducting phase with non-Hermiticity.

Abstract

Studying the immunity of topological superconductors against non-local disorder is one of the key issues in both fundamental researches and potential applications. Here, we demonstrate that the non-Hermiticity can enhance the robustness of topological edge states against non-local disorder. To illustrate that, we consider a one-dimensional (1D) generalized Kitaev model with the asymmetric hopping in the presence of disorder. It is shown that the region supporting Majorana zero modes (MZMs) against non-local disorder will be enlarged by the non-Hermiticity. Through both the numerical and analytical analyses, we show that non-Hermiticity can stabilize the topological superconducting (SC) phase against higher disorder strength. Our studies would offer new insights into the interplay between non-Hermiticity and topology.