Nonlinear photoluminescence in atomically thin layered WSe2 arising from diffusion-assisted exciton-exciton annihilation

We studied multiexciton 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 micrometer...

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Bibliographic Details
Main Authors: Mouri, Shinichiro, Miyauchi, Yuhei, Toh, Minglin, Zhao, Weijie, Eda, Goki, Matsuda, Kazunari
Other Authors: School of Materials Science & Engineering
Format: Journal Article
Language:English
Published: 2014
Subjects:
Online Access:https://hdl.handle.net/10356/102413
http://hdl.handle.net/10220/24269
Description
Summary:We studied multiexciton 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 (EEA) model accounts for the observed nonlinear PL behavior. The long-distance exciton diffusion and subsequent efficient EEA process determined the unusual multiexciton dynamics in atomically thin layered transition metal dichalcogenides.