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Decay and coherence of two-photon excited yellow ortho-excitons in Cu2O

K. Karpinska·M. Mostovoy·M. A. van der Vegte·A. Revcolevschi·P. H. M. van Loosdrecht
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Abstract

Photoluminescence excitation spectroscopy has revealed a novel, highly efficient two-photon excitation method to produce a cold, uniformly distributed high density excitonic gas in bulk cuprous oxide. A study of the time evolution of the density, temperature and chemical potential of the exciton gas shows that the so called quantum saturation effect that prevents Bose-Einstein condensation of the ortho-exciton gas originates from an unfavorable ratio between the cooling and recombination rates. Oscillations observed in the temporal decay of the ortho-excitonic luminescence intensity are discussed in terms of polaritonic beating. We present the semiclassical description of polaritonic oscillations in linear and non-linear optical processes.

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K. Karpinska, M. Mostovoy, M. A. van der Vegte, A. Revcolevschi, P. H. M. van Loosdrecht. 2005-05-15. Decay and coherence of two-photon excited yellow ortho-excitons in Cu2O. https://doi.org/10.1103/physrevb.72.155201

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