Strong coupling of polaritons at room temperature in a GaAs/AlGaAs structure

TL;DR

This paper demonstrates strong coupling of polaritons at room temperature in GaAs/AlGaAs microcavities, showing potential for room-temperature polaritonic devices with high-quality material systems.

Contribution

It provides the first direct measurement of polariton dispersion at room temperature in GaAs/AlGaAs structures, confirming strong coupling and exciton retention in high-density regimes.

Findings

Polariton dispersion clearly shows strong coupling at room temperature.

Rabi splitting decreases with increasing polariton density.

Polaritons retain a strong exciton component even in Bose-condensate-like states.

Abstract

We report direct measurement of the dispersion relation of polaritons in GaAs/AlGaAs microcavity structures at room temperature, which clearly shows that the polaritons are in the strong coupling limit. The Rabi splitting of the polariton states decreases as the polariton gas increases in density, but even when the polariton gas becomes a coherent, Bose-condensate-like state, the polaritons retain a strong exciton component, as seen in the nonlinear energy shift of the light emission. This opens up the possibility of polaritonic devices at room temperature in a material system which can be grown with very high quality and uniformity.