General pairing mechanisms in the BCS-theory of superconductivity

TL;DR

This paper explores generalized pairing mechanisms in BCS superconductivity, showing that pairing can occur with non-zero total momentum, expanding the understanding of pairing interactions beyond traditional models.

Contribution

It introduces the concept that pairing can happen with particles having non-zero total momentum within the BCS framework, highlighting new possible pairing scenarios.

Findings

Pairing can occur with particles having non-zero total momentum.

Effective interactions in center-of-mass coordinates enable alternative pairing.

The linearized BdG-equation supports these generalized pairing mechanisms.

Abstract

Starting from the linearized BdG-equation we make the simple observation that pairing can occur between particles with total momenta different from zero, e.g., with equal momentum and opposite spin, in cases of an effective interaction acting in the center-of-mass coordinates.