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arXiv · 0807.4964

Signature of the microcavity exciton-polariton relaxation mechanism in the polarization of emitted light

Georgios Roumpos·Chih-Wei Lai·T. C. H. Liew·Yuri G. Rubo·A. V. Kavokin·Yoshihisa Yamamoto
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Abstract

We have performed real and momentum space spin-dependent spectroscopy of spontaneously formed exciton polariton condensates for a non-resonant pumping scheme. Under linearly polarized pump, our results can be understood in terms of spin-dependent Boltzmann equations in a two-state model. This suggests that relaxation into the ground state occurs after multiple phonon scattering events and only one polariton-polariton scattering. For the circular pumping case, in which only excitons of one spin are injected, a bottleneck effect is observed, implying inefficient relaxation.

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Georgios Roumpos, Chih-Wei Lai, T. C. H. Liew, Yuri G. Rubo, A. V. Kavokin, Yoshihisa Yamamoto. 2009-05-11. Signature of the microcavity exciton-polariton relaxation mechanism in the polarization of emitted light. https://doi.org/10.1103/physrevb.79.195310

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