Excitonic condensation in quasi-two-dimensional systems

TL;DR

This paper develops a low energy theoretical model to describe excitonic Bose-Einstein condensation in quasi-two-dimensional systems, analyzing critical properties and potential experimental relevance.

Contribution

It introduces a $ ext{Phi}^4$ model with dynamical critical exponent $z=2$ and uses renormalization group flow equations to study condensation phenomena.

Findings

Calculated temperature dependence of critical density, coherence length, magnetic susceptibility, and specific heat.

Model potentially explains macroscopic coherence observed in GaAs/AlGaAs quantum wells.

Provides a theoretical framework for excitonic condensation in low-dimensional systems.

Abstract

We present a low energy model for the Bose-Einstein condensation in a quasi-two-dimensional excitonic gas. Using the flow equations of the Renormalization group and a $\Phi^4$ model with the dynamical critical exponent $z=2$ we calculate the temperature dependence of the critical density, coherence length, magnetic susceptibility, and specific heat. The model can be relevant for the macroscopic coherence observed in GaAs/AlGaAs coupled quantum wells.