Interaction effects on proximity-induced superconductivity in semiconducting nanowires

TL;DR

This paper analyzes how electron-electron interactions influence proximity-induced superconductivity in semiconducting nanowires, revealing conditions that could enable topological superconducting states in coupled wire systems.

Contribution

It provides an analytic expression for the effective pairing potential considering interactions, advancing understanding of interaction effects in nanowire-based superconductors.

Findings

Interactions reduce pairing energy in nanowires.

Interaction effects can enhance interwire pairing potential.

Potential for realizing topological superconductivity in coupled nanowires.

Abstract

We investigate the effect of electron-electron interactions on proximity-induced $s$-wave superconductivity in one-dimensional nanowires. We treat the interactions on a self-consistent mean-field level, and find an analytic expression for the effective pairing potential in the presence of interactions, valid for a weakly tunnel coupled wire. We show that for a set of two nanowires placed in parallel on a superconducting substrate, the interaction-induced reduction of the pairing energy could result in the effective interwire pairing potential exceeding the intrawire potential, which is one of the requirements for creating a time-reversal symmetric topological superconducting state in such a two-wire system.