Phase Structure of a Four- and Eight-Fermion Interaction Model at Finite Temperature and Chemical Potential in Arbitrary Dimensions

TL;DR

This paper explores how four- and eight-fermion interactions influence phase transitions at finite temperature and chemical potential across various dimensions, revealing modifications to phase boundaries caused by higher-order interactions.

Contribution

It provides a detailed analysis of the phase structure in a fermion interaction model, incorporating eight-fermion interactions and their effects on phase boundaries in arbitrary dimensions.

Findings

Eight-fermion interaction modifies the phase boundary during first order phase transitions.

The effective potential and gap equation are derived in the leading order of 1/N expansion.

The phase structure is analyzed in dimensions between 2 and 4.

Abstract

The phase structure of a four- and eight-fermion interaction model is investigated at finite temperature and chemical potential in arbitrary space-time dimensions, $2\leq D<4$. The effective potential and the gap equation are calculated in the leading order of the 1/N expansion. If the first order phase transition takes place, the phase boundary dividing the symmetric and the broken phase is modified by the eight-fermion interaction.