Competition between superconductivity and nematic order : anisotropy of superconducting coherence length

TL;DR

This paper investigates how nematic order influences superconducting coherence length anisotropy, revealing a strong enhancement beyond traditional theories, supported by universal coupling functions and experimental relevance.

Contribution

It introduces universal functions describing the coupling between nematic order and superconductivity, highlighting a significant anisotropy enhancement beyond Ginzburg-Landau expectations.

Findings

Nematic order significantly enhances superconducting coherence length anisotropy.

Universal functions describe the coupling between nematic order and superconductivity.

Results connect to experimental observations in FeSe.

Abstract

We study the interplay between nematic order and superconductivity, motivated by a recent experiment on FeSe observing strongly distorted vortex shapes (Song et al., Science 332, 1410 (2011)). We show that the nematic order strongly enhances the anisotropy in the superconducting coherence length, beyond that expected from considerations of the Ginzburg-Landau theory. We obtain universal functions describing the coupling between the nematic order and superconductivity, and discuss connections of our results to the experiments.