Properties of the massive Gross-Neveu model with nonzero baryon and isospin chemical potentials

TL;DR

This paper explores the phase structure, quasiparticle excitations, and mesonic spectrum of the two-flavored Gross-Neveu model at finite isospin and quark chemical potentials in (1+1) dimensions, revealing complex phase behavior.

Contribution

It provides a detailed analysis of the phase diagram and excitation spectrum of the massive Gross-Neveu model with nonzero chemical potentials, extending understanding of its rich phase structure.

Findings

Identified phases with and without pion condensation.

Discovered various gapless and gapped quasiparticle excitations.

Analyzed mesonic mass spectrum across different phases.

Abstract

The properties of the two-flavored Gross-Neveu model with nonzero current quark mass are investigated in the (1+1)-dimensional spacetime at finite isospin $\mu_I$ as well as quark number $\mu$ chemical potentials and zero temperature. The consideration is performed in the limit $N_c\to\infty$, i.e. in the case with an infinite number of colored quarks. In the plane of parameters $\mu_I,\mu$ a rather rich phase structure is found, which contains phases with and without pion condensation. We have found a great variety of one-quark excitations of these phases, including gapless and gapped quasiparticles. Moreover, the mesonic mass spectrum in each phase is also investigated.