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arXiv · 0807.3224

Observation of long-lived polariton states in semiconductor microcavities across the parametric threshold

D. Ballarini·D. Sanvitto·A. Amo·L. Vina·M. Wouters·I. Carusotto·A. Lemaitre·J. Bloch
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Abstract

The excitation spectrum around the pump-only stationary state of a polariton optical parametric oscillator (OPO) in semiconductor microcavities is investigated by time-resolved photoluminescence. The response to a weak pulsed perturbation in the vicinity of the idler mode is directly related to the lifetime of the elementary excitations. A dramatic increase of the lifetime is observed for a pump intensity approaching and exceeding the OPO threshold. The observations can be explained in terms of a critical slowing down of the dynamics upon approaching the threshold and the following onset of the soft Goldstone mode.

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D. Ballarini, D. Sanvitto, A. Amo, L. Vina, M. Wouters, I. Carusotto, A. Lemaitre, J. Bloch. 2008-07-21. Observation of long-lived polariton states in semiconductor microcavities across the parametric threshold. https://doi.org/10.1103/physrevlett.102.056402

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