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Polariton condensation with localised excitons and propagating photons

Jonathan Keeling·P. R. Eastham·M. H. Szymanska·P. B. Littlewood
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Abstract

We estimate the condensation temperature for microcavity polaritons, allowing for their internal structure. We consider polaritons formed from localised excitons in a planar microcavity, using a generalised Dicke model. At low densities, we find a condensation temperature T_c \propto ρ, as expected for a gas of structureless polaritons. However, as T_c becomes of the order of the Rabi splitting, the structure of the polaritons becomes relevant, and the condensation temperature is that of a B.C.S.-like mean field theory. We also calculate the excitation spectrum, which is related to observable quantities such as the luminescence and absorption spectra.

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Jonathan Keeling, P. R. Eastham, M. H. Szymanska, P. B. Littlewood. 2004-11-11. Polariton condensation with localised excitons and propagating photons. https://doi.org/10.1103/physrevlett.93.226403

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