Supercurrent-induced topological phase transitions

TL;DR

This paper demonstrates that applying a finite supercurrent can induce topological phase transitions in various superconducting systems by deforming their quasiparticle spectra, with potential experimental implications.

Contribution

It introduces a universal mechanism where supercurrent causes topological phase transitions across different superconductors, expanding understanding of current-induced topological phenomena.

Findings

All studied models exhibit current-induced topological phase transitions.

Finite COM momentum acts as an external field triggering topological changes.

Discussion on experimental observation of these phase transitions.

Abstract

We show that finite current in superconductors can induce topological phase transitions, as a result of the deformation of the quasiparticle spectrum by a finite center-of-mass (COM) momentum of the Cooper pairs. To show the wide applicability of this mechanism, we examine the topological properties of three prototypical systems, the Kitaev chain, $s$-wave superconductors, and $d$-wave superconductors. We introduce a finite COM momentum as an external field corresponding to supercurrent and show that all the models exhibit current-induced topological phase transitions. We also discuss the possibility of observing the phase transitions in experiments and the relation to the other finite COM momentum pairing states.