Critical Temperature Enhancement of Topological Superconductors: A Dynamical Mean Field Study

TL;DR

This study demonstrates how the interplay of Zeeman magnetic field and Rashba spin-orbit coupling can enhance the critical temperature of topological superconductors, using advanced dynamical mean field theory methods.

Contribution

It introduces a novel mechanism for Tc enhancement in topological superconductors through magnetic field and spin-orbit coupling cooperation, evaluated with DMFT and quantum Monte Carlo techniques.

Findings

Critical temperature Tc is enhanced by magnetic field and spin-orbit coupling.

Spin-flip driven local pair hopping contributes to Tc enhancement.

Proposed experimental setups include Si(111) monolayers and ionic-liquid EDLTs.

Abstract

We show that a critical temperature Tc for spin-singlet two-dimensional superconductivity is enhanced by a cooperation between the Zeeman magnetic field and the Rashba spin-orbit coupling, where a superconductivity becomes topologically non-trivial below Tc. The dynamical mean field theory (DMFT) with the segment-based hybridization-expansion continuous-time quantum Monte Carlo impurity solver (ct-HYB) is used for accurately evaluating a critical temperature, without any Fermion sign problem. A strong-coupling approach shows that spin-flip driven local pair hopping leads to part of this enhancement, especially effects of the magnetic field. We propose physical settings suitable for verifying the present calculations, one-atom-layer system on Si(111) and ionic-liquid based electric double-layer transistors (EDLTs).