Effective Potential and Thermodynamics for a Coupled Two-Field Bose Gas Model

TL;DR

This paper investigates the thermodynamics of a two-species Bose gas with self-interactions and quadratic coupling, analyzing phase transitions, symmetry breaking, and reentrant phenomena using field theory techniques.

Contribution

It introduces a detailed finite-temperature effective potential analysis for coupled two-field Bose gases, highlighting novel phase behavior and critical temperature shifts.

Findings

Identification of reentrant phases in coupled Bose gases

Observation of shifts in critical temperatures due to inter-species coupling

Analysis of symmetry breaking patterns depending on coupling strengths

Abstract

We study the thermodynamics of a two-species homogeneous and dilute Bose gas that is self-interacting and quadratically coupled to each other. We make use of field theoretical functional integral techniques and evaluate the one-loop finite temperature effective potential for this system considering the resummation of the leading order temperature dependent as well as infrared contributions. The symmetry breaking pattern associated to the model is then studied by considering different values of self and inter-species couplings. We pay special attention to the eventual appearance of reentrant phases and/or shifts in the observed critical temperatures as compared to the monoatomic (one-field Bose) case.