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arXiv · 1705.03135

A Model to Study Finite-Size and Magnetic Effects on the Phase Transition of a Fermion Interacting System

Emerson B. S. Corrêa·César A. Linhares·Adolfo P. C. Malbouisson
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Abstract

We present a model to study effects from an external magnetic field, chemical potential, and finite size, on the phase structure of a massive four- and six-fermion interacting system. These effects are introduced by a method of compactification of coordinates, a generalization of the standard Matsubara prescription. Through the compactification of the $z$ coordinate and of imaginary time, we describe a heated system with the shape of a film of thickness $L$, at temperature $\beta^{-1}$ undergoing first- or second-order phase transition. We have found a strong dependence of the temperature transition on the constants couplings $\lambda$ and $\eta$. Besides magnetic catalysis and symmetry breaking for both kinds of transition, we have found an inverse symmetry breaking phenomenon with respect to first-order phase transition.

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Emerson B. S. Corrêa, César A. Linhares, Adolfo P. C. Malbouisson. 2017-05-09. A Model to Study Finite-Size and Magnetic Effects on the Phase Transition of a Fermion Interacting System. https://doi.org/10.1142/s0217979218500911

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