Thermodynamic model of the macroscopically ordered exciton state

TL;DR

This paper presents a thermodynamic model explaining the formation of a macroscopically ordered exciton state in cold exciton gases, highlighting phase fluctuations and a second order phase transition.

Contribution

It introduces a thermodynamic framework that accounts for phase fluctuations to explain MOES formation and its temperature-dependent energy behavior.

Findings

Observation of MOES in cold exciton gases

Identification of second order phase transition signature

Scaling behavior of exciton energy with temperature

Abstract

We explain the experimentally observed instability of cold exciton gases and formation of a macroscopically ordered exciton state (MOES) in terms of a thermodynamic model accounting for the phase fluctuations of the condensate. We show that the temperature dependence of the exciton energy exhibits fundamental scaling behavior with the signature of the second order phase transition.