Controlled Switching of Bose-Einstein Condensation in a Mixture of Two Species of Polaritons

TL;DR

This study demonstrates temperature-controlled switching between lower and upper polariton Bose-Einstein condensates in a microcavity, revealing temperature-dependent stability and metastability phenomena in polariton mixtures.

Contribution

It introduces a method to control polariton condensation states via temperature in a two-species polariton system.

Findings

Condensation switches from lower to upper polariton with increasing temperature.

Metastable correlations observed at intermediate temperatures.

Condensation behavior depends on temperature and relative populations.

Abstract

We report temperature-dependent switching between lower and upper polariton condensation in a GaAs/AlGaAs microcavity when both of these species have comparable populations in a mixture. Using angle-resolved photoluminescence, we observe that at low temperatures, condensation occurs in the lower polariton branch, while at elevated temperatures, the upper polariton branch can become favored. At an intermediate temperature, we observe instability in the condensate formation, characterized by metastable correlations of the fluctuations in intensity and linewidth of the lower and upper polariton branches.