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arXiv · 1301.4838

Second Thresholds in BEC-BCS-Laser Crossover of Exciton-Polariton Systems

Makoto Yamaguchi·Kenji Kamide·Ryota Nii·Tetsuo Ogawa·Yoshihisa Yamamoto
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Abstract

The mechanism of second thresholds observed in several experiments is theoretically revealed by studying the BEC-BCS-laser crossover in exciton-polariton systems. We found that there are two different types for the second thresholds; one is a crossover within quasi-equilibrium phases and the other is into non-equilibrium (lasing). In both cases, the light-induced band renormalization causes gaps in the conduction and valence bands, which indicates the exsistence of bound electron-hole pairs in contrast to earlier expectations. We also show that these two types can be distinguished by the gain spectra.

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Makoto Yamaguchi, Kenji Kamide, Ryota Nii, Tetsuo Ogawa, Yoshihisa Yamamoto. 2014-12-12. Second Thresholds in BEC-BCS-Laser Crossover of Exciton-Polariton Systems. https://doi.org/10.1103/physrevlett.111.026404

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