Condition For Gapless Color-Antitriplet Excitations In Nambu-Jona-Lasinio Models

Abstract

We present an exact condition for the existence of gapless quasiparticle excitations in Nambu-Jona-Lasinio models of color superconducting quark matter with a quark-quark interaction in the scalar color-antitriplet channel. The condition can be represented by a rotated ellipse in the plane of mass and chemical potential differences for the paired quark fields.