Tricritical curve of massive chiral Gross-Neveu model with isospin

TL;DR

This paper refines the phase diagram of the two-flavor massive chiral Gross-Neveu model in 1+1 dimensions by precisely determining the tricritical curves using advanced perturbation theory.

Contribution

It provides the exact determination of tricritical curves in the phase diagram, extending previous analyses with a novel stability analysis method.

Findings

Exact tricritical curves for three different bare masses

Enhanced understanding of phase transitions in the model

Extension of stability analysis techniques

Abstract

We reconsider the two-flavor version of the massive, chiral Gross-Neveu model in 1+1 dimensions. Its phase diagram as a function of baryon chemical potential, isospin chemical potential and temperature has previously been explored. We recapitulate the results, adding the missing tricritical curves. They can be determined exactly by extending the standard stability analysis, using fourth order almost degenerate perturbation theory. Results for three different bare masses are presented and discussed.