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Origin of the inner ring in photoluminescence patterns of quantum well excitons

A. L. Ivanov·L. E. Smallwood·A. T. Hammack·Sen Yang·L. V. Butov·A. C. Gossard
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Abstract

In order to explain and model the inner ring in photoluminescence (PL) patterns of indirect excitons in GaAs/AlGaAs quantum wells (QWs), we develop a microscopic approach formulated in terms of coupled nonlinear equations for the diffusion, thermalization and optical decay of the particles. The origin of the inner ring is unambiguously identified: it is due to cooling of indirect excitons in their propagation from the excitation spot. We infer that in our high-quality structures the in-plane diffusion coefficient is about 10-30cm^2/s and the amplitude of the disorder potential is about 0.45meV.

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A. L. Ivanov, L. E. Smallwood, A. T. Hammack, Sen Yang, L. V. Butov, A. C. Gossard. 2005-09-05. Origin of the inner ring in photoluminescence patterns of quantum well excitons. https://doi.org/10.1209/epl%2Fi2006-10002-4

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