Unlocking interband phase difference in multiband superconductors

Abstract

Chiral fluctuation in frustrated superconductivity unlocks the interband phase difference at the superconducting transition temperature calculated by the standard Bardeen-Cooper-Schrieffer (BCS) theory when an interband interaction is much weaker than an intraband interaction. At low temperature, a first-order phase transition locks the interband phase difference. This transition is demonstrated in degenerate chiral superconductivity, which adds a pair entropy term to the BCS theory. © 2012 Elsevier B.V. All rights reserved.