Piezo-superconductivity: new effects in non-centrosymmetric superconductors

TL;DR

This paper explores novel effects in non-centrosymmetric superconductors, revealing how their unique coupling mechanisms lead to fractional magnetic flux in dislocations and strain generation in Josephson junctions, expanding understanding of superconducting phenomena.

Contribution

It introduces the concept that Lifshitz coupling, previously thought unobservable in bulk, causes fractional flux in dislocations and predicts strain effects in Josephson junctions, linking superconductivity with higher-form symmetries.

Findings

Dislocations carry fractional magnetic flux due to Lifshitz coupling.

DC current induces voltage-free strain in P and T-breaking Josephson junctions.

Lifshitz coupling acts as a chemical potential for winding number, analogous to pyroelectric insulators.

Abstract

We study novel effects in non-centrosymmetric superconductors arising from their unique coupling of Cooper-pair condensate and elasticity. We show that although the much discussed Lifshitz coupling is not observable in a uniform bulk state, it strikingly endows dislocations with a fractional magnetic flux. We also predict a generation of voltage-free strain by a DC current in a P and T-breaking Josephson junction. Viewing superconductors through the lens of higher-form symmetries we identify the Lifshitz coupling as a chemical potential for the approximately conserved winding number, drawing an analogy with pyroelectric insulators.