Spontaneous formation of a polariton condensate in a planar GaAs microcavity

Abstract
We report on polaritoncondensation in a planar GaAsmicrocavity under nonresonant optical excitation. Angularly resolved photoluminescence measurements demonstrate polaritoncondensation for temperature up to 40 K. Numerical simulations using Boltzmann equations give an overall description of the observed condensation for various detunings and temperatures. This model highlights the importance of the polariton relaxation rate as compared to the polariton decay for condensation to occur on the lowest energy polariton states.