Temporal fluctuation induced order in conventional superconductors

TL;DR

This paper reveals that temporal fluctuations in conventional superconductors induce a form of order, leading to a broadening of the superconducting gap in momentum space and a smooth transition from BCS to BEC regimes.

Contribution

It introduces the concept that temporal oscillations of the superconducting gap promote communal pairing via order by disorder, a novel mechanism in superconductivity.

Findings

Superconducting gap width increases with interaction strength.

Temporal oscillations stabilize finite momentum space width.

Smooth BCS to BEC evolution observed.

Abstract

Communal pairing in superconductors introduces variational freedom for Cooper pairs to share fermions. Temporal oscillations of the superconducting gap entropically drive communal pairing through the order by disorder phenomenology, stabilising a finite momentum space width of the superconducting gap that increases with interaction strength, creating a smooth evolution from the weakly interacting BCS state to the strongly interacting BEC state.