Magnetic stability analysis for Abelian and non-Abelian superconductors

Abstract

We investigate the origin of Abelian and non-Abelian type magnetic instabilities induced by the Fermi surface mismatch between the two pairing fermions in a nonrelativistic model. The Abelian type instability occurs only in a gapless state and the Meissner mass squared becomes divergent at the gapless-gapped transition point, while the non-Abelian type instability happens in both gapless and gapped states and the divergence vanishes. The non-Abelian type instability can be cured in a strong coupling region.