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arXiv · 1405.5781

Nonlinear Photoluminescence in Atomically Thin Layered WSe2 Arising from Diffusion-Assisted Exciton-Exciton Annihilation

Shinichiro Mouri·Yuhei Miyauchi·Minglin Toh·Weijie Zhao·Goki Eda·Kazunari Matsuda
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Abstract

We studied multi-exciton dynamics in monolayer WSe2 using nonlinear photoluminescence (PL) spectroscopy and Monte Carlo simulations. We observed strong nonlinear saturation behavior of exciton PL with increasing excitation power density, and long-distance exciton diffusion reaching several micrometers. We demonstrated that the diffusion-assisted exciton-exciton annihilation model accounts for the observed nonlinear PL behavior. The long-distance exciton diffusion and subsequent efficient exciton-exciton annihilation process determined the unusual multi-exciton dynamics in atomically thin layered transition metal dichalcogenides.

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Shinichiro Mouri, Yuhei Miyauchi, Minglin Toh, Weijie Zhao, Goki Eda, Kazunari Matsuda. 2014-05-22. Nonlinear Photoluminescence in Atomically Thin Layered WSe2 Arising from Diffusion-Assisted Exciton-Exciton Annihilation. https://doi.org/10.1103/physrevb.90.155449

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