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Finite-size fluctuations and photon statistics near the polariton condensation transition in a single-mode microcavity

P. R. Eastham·P. B. Littlewood
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Abstract

We consider polariton condensation in a generalized Dicke model, describing a single-mode cavity containing quantum dots, and extend our previous mean-field theory to allow for finite-size fluctuations. Within the fluctuation-dominated regime the correlation functions differ from their (trivial) mean-field values. We argue that the low-energy physics of the model, which determines the photon statistics in this fluctuation-dominated crossover regime, is that of the (quantum) anharmonic oscillator. The photon statistics at the crossover are different in the high- and low- temperature limits. When the temperature is high enough for quantum effects to be neglected we recover behavior similar to that of a conventional laser. At low enough temperatures, however, we find qualitatively different behavior due to quantum effects.

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P. R. Eastham, P. B. Littlewood. 2006-02-07. Finite-size fluctuations and photon statistics near the polariton condensation transition in a single-mode microcavity. https://doi.org/10.1103/physrevb.73.085306

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