Asymmetric superconductivity in metallic systems

摘要: Different types of superfluid ground states have been investigated in systems two species fermions with Fermi surfaces that do not match. This study is relevant for cold atomic systems, condensed matter physics and quark matter. In this paper we consider problem the case fermionic quasi-particles can transmute into one another only their total number conserved. We use a BCS approximation to superconductivity two-band metallic inter intra-band interactions. Tuning hybridization between bands varies mismatch produces different instabilities. For inter-band attractive interactions find first order normal-superconductor homogeneous metastable phase gapless excitations. interactions, transition from superconductor normal state as increases continuous associated quantum critical point. The when both are present also considered.