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# Intrinsic decoherence mechanisms in the microcavity polariton condensate

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Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, United Kingdom.
(Impact Factor: 7.73). 09/2008; 101(6):067404. DOI: 10.1103/PhysRevLett.101.067404
Source: PubMed

ABSTRACT The fundamental mechanisms which control the phase coherence of the polariton Bose-Einstein condensate (BEC) are determined. It is shown that the combination of number fluctuations and interactions leads to decoherence with a characteristic Gaussian decay of the first-order correlation function. This line shape, and the long decay times ( approximately 150 ps) of both first- and second-order correlation functions, are explained quantitatively by a quantum-optical model which takes into account interactions, fluctuations, and gain and loss in the system. Interaction limited coherence times of this type have been predicted for atomic BECs, but are yet to be observed experimentally.

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