Dynamically Generated Fermi Surface Mismatch and Relativistic Superfluidity in a Two-Component Massless Fermionic Theory

Abstract

When fermions pair across mismatched Fermi surfaces, the mismatch reflects a built-in inequivalence between the species. We show it can instead arise dynamically by spontaneous symmetry breaking. In a massless two component Dirac theory with exact SU(2) flavor symmetry, a self-interacting vector boson condenses, splitting the Fermi surfaces while preserving time reversal. Pairing then yields a stable relativistic superfluid, promoting the Chandrasekhar-Clogston line to a surface in coupling space, the mismatch fixed self-consistently by the symmetry-breaking coupling.