The Ginzburg-Landau Equation for³<i>P</i>₂Pairing

Abstract

The purpose of this work is to study superfluid properties of a neutral fermion system with pairing in a non-zero angular momentum state, in particular, with sp2 pairing expected in neutron stars. The gap equation and the equation of the Ginzburg-Landau (G-L) type are derived for general pairing. We then specialize to the caseof 8P 2 pairing and present the G-L equation for the five component order parameter in the form of a non-linear field equation for a spin 2 field. The expressions for the free energy, the current density and the angular momentum density are found in terms of the order parameter. With the help of the G-L equation some features of vortex states are discussed.