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Study of ortho-to-paraexciton conversion in Cu$_2$O by excitonic Lyman spectroscopy

M. Kubouchi·K. Yoshioka·R. Shimano·A. Mysyrowicz·M. Kuwata-Gonokami
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Abstract

Using time-resolved $1s$-$2p$ excitonic Lyman spectroscopy, we study the orthoexciton-to-paraexcitons transfer, following the creation of a high density population of ultracold $1s$ orthoexcitons by resonant two-photon excitation with femtosecond pulses. An observed fast exciton-density dependent conversion rate is attributed to spin exchange between pairs of orthoexcitons. Implication of these results on the feasibility of BEC of paraexcitons in Cu$_2$O is discussed.

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M. Kubouchi, K. Yoshioka, R. Shimano, A. Mysyrowicz, M. Kuwata-Gonokami. 2005-01-14. Study of ortho-to-paraexciton conversion in Cu$_2$O by excitonic Lyman spectroscopy. https://doi.org/10.1103/physrevlett.94.016403

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