Two-color QCD with staggered fermions at finite temperature under the influence of a magnetic field

TL;DR

This study explores how a constant magnetic field affects the finite-temperature phase structure and chiral properties of a simplified SU(2) lattice QCD model with staggered fermions, revealing magnetic field-induced changes in critical temperature and chiral condensate behavior.

Contribution

It provides new insights into the magnetic field's impact on phase transitions and chiral symmetry breaking in a simplified lattice QCD model with dynamical fermions.

Findings

Critical temperature increases with magnetic field strength.

Chiral condensate grows monotonically with magnetic field in the broken phase.

Chiral condensate approaches zero in the restored phase, regardless of magnetic field.

Abstract

In this paper we investigate the influence of a constant external magnetic field on the finite-temperature phase structure and the chiral properties of a simplified lattice model for QCD. We assume an SU(2) gauge symmetry and employ dynamical staggered fermions of identical mass without rooting, corresponding to Nf=4 flavors of identical electric charge. For fixed mass (given in lattice units) the critical temperature is seen to rise with the magnetic field strength. For three fixed beta-values, selected such that we stay (i) within the chirally broken phase, (ii) within the transition region or (iii) within the chirally restored phase, we study the approach to the chiral limit for various values of the magnetic field. Within the chirally broken (confinement) phase the chiral condensate is found to increase monotonically with a growing magnetic field strength. In the chiral limit the increase starts linear in agreement with a chiral model studied by Shushpanov and Smilga. Within the chirally restored (deconfinement) phase the chiral condensate tends to zero in the chiral limit, irrespective of the strength of the magnetic field.