Spontaneous magnetization in QCD and non-Fermi-liquid effects

TL;DR

This paper investigates the magnetic properties of quark matter at finite temperature, revealing non-Fermi-liquid effects and identifying a critical temperature for magnetic phase transition through a combined microscopic and Fermi-liquid theoretical approach.

Contribution

It introduces a novel analysis of quark matter magnetization incorporating dynamic gluon screening effects, highlighting non-Fermi-liquid behavior in magnetic susceptibility.

Findings

Identification of a $T^2 \, \ln T$ term in magnetic susceptibility

Determination of the Curie temperature for quark matter

Construction of the magnetic phase diagram in density-temperature space

Abstract

Magnetic properties of quark matter at finite temperature are discussed by evaluating the magnetic susceptibility. Combining the microscopic calculation of the self-energy for quarks as well as the screening effects for gluons with Fermi-liquid theory in a consistent way, we study the temperature dependence of the magnetic susceptibility. The longitudinal gluons have the static screening given by the Debye mass, and have a standard temperature dependence of $O(T^2)$. An anomalous $T^2\ln T$ term arises in the magnetic susceptibility as a novel non-Fermi-liquid effect due to the anomalous self-energy for quarks given by the dynamic screening for transverse gluons. We then extract the critical(Curie) temperature and present the magnetic phase diagram on the density-temperature plane.