Reentrant topological transitions in a quantum wire/superconductor system with quasiperiodic lattice modulation

TL;DR

This paper investigates how quasiperiodic lattice modulation induces reentrant topological superconductor phases with Majorana modes in a quantum wire, revealing complex phase transitions and band structures.

Contribution

It demonstrates the emergence of multiple reentrant topological phases in a quantum wire with quasiperiodic modulation using density-matrix renormalization group analysis.

Findings

Multiple topological phases with Majorana modes are realized.

Reentrant transitions occur as the chemical potential varies.

Band structures exhibit self-similar patterns.

Abstract

We study the condition for a topological superconductor (TS) phase with end Majorana fermions to appear when a quasiperiodic lattice modulation is applied to a one-dimensional quantum wire with strong spin-orbit interaction situated under a magnetic field and in proximity to a superconductor. By density-matrix renormalization group analysis, we find that multiple topological phases with Majorana end modes are realized in finite ranges of the filling factor, showing a sequence of reentrant transitions as the chemical potential is tuned. The locations of these phases reflect the structure of bands in the non-interacting case, which exhibits a distinct self-similar structure. The stability of the TS in the presence of an on-site interaction or a harmonic trap potential is also discussed.