Parity-time-symmetric topological superconductor

TL;DR

This paper explores a non-Hermitian topological superconductor with balanced gain and loss, revealing unique edge modes and nonlocal particle transport arising from the interplay of parity-time symmetry and topology.

Contribution

It introduces a non-Hermitian Kitaev chain model exhibiting unconventional edge modes with complex energies and nonorthogonal Majorana zero modes, advancing understanding of topological superconductivity under non-Hermitian conditions.

Findings

Identification of edge modes with complex energies.

Observation of nonlocal particle transport at edges.

Demonstration of interplay between PT symmetry and topological phases.

Abstract

We investigate a topological superconducting wire with balanced gain and loss that is effectively described by the non-Hermitian Kitaev/Majorana chain with parity-time symmetry. This system is shown to possess two distinct types of unconventional edge modes, those with complex energies and nonorthogonal Majorana zero modes. The latter edge modes cause nonlocal particle transport with currents that are localized at the edges and absent in the bulk. This anomalous particle transport results from the interplay between parity-time symmetry (non-Hermiticity) and topological superconductivity.