Nonlocal transport phenomena in coupled quasiperiodic Kitaev chains

TL;DR

This paper explores topological phases and Majorana edge modes in a coupled quasiperiodic Kitaev chain, revealing new phase transitions influenced by quasiperiodicity and analyzing conductance dependence on connection patterns.

Contribution

It elucidates the topological phases in coupled quasiperiodic Kitaev chains and demonstrates how quasiperiodicity induces new topological phase transitions.

Findings

Emergence of topological phases with Majorana edge modes

Dependence of differential conductance on lead connection pattern

Identification of a new quasiperiodicity-induced topological phase transition

Abstract

We investigate the topological phases in a coupled one-dimensional p-wave superconducting Fibonacci quasicrystal modeled by the quasiperiodic Kitaev chain. Recent studies have shown that the coupled system can host topological edge modes with Majorana fermions and enhance their topological protection, depending on the pattern of quasiperiodicity. In this work, we elucidate the topological phases of the coupled system and demonstrate the dependence of differential conductance on the lead connecting pattern employing the Keldysh formalism and the recursive Green's function method. Our findings reveal the emergence of topological phases in the coupled system, which are characterized by the presence of Majorana edge modes and the seepage of the Majorana wave function. Furthermore, we identify a new topological phase transition induced by quasiperiodicity in the coupled system.