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arXiv · 1504.07147

Exciton spin dynamics in GaSe

Yanhao Tang·Wei Xie·Krishna C. Mandal·John A. McGuire·Chih-Wei Lai
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Abstract

We analyze exciton spin dynamics in GaSe under nonresonant circularly polarized optical pumping with an exciton spin-flip rate-equation model. The model reproduces polarized time-dependent photoluminescence measurements in which the initial circular polarization approaches unity even when pumping with 0.15 eV excess energy. At T = 10 K, the exciton spin relaxation exhibits a biexponential decay with a sub-20 ps and a >500 ps time constants, which are also reproduced by the rate-equation model assuming distinct spin-relaxation rates for hot (nonequilibrium) and cold band-edge excitons.

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Yanhao Tang, Wei Xie, Krishna C. Mandal, John A. McGuire, Chih-Wei Lai. 2015-06-05. Exciton spin dynamics in GaSe. https://doi.org/10.1063/1.4930809

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