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arXiv · 1201.2574

Imaging ambipolar diffusion of photocarriers in GaAs thin films

Daniel Paget·Fabian Cadiz·Alistair Rowe·Francois Moreau·Steve Arscott·Emilien Peytavit
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Abstract

Images of the steady-state luminescence of passivated GaAs self-standing films under excitation by a tightly-focussed laser are analyzed as a function of light excitation power. While unipolar diffusion of photoelectrons is dominant at very low light excitation power, an increased power results in a decrease of the diffusion constant near the center of the image due to the onset of ambipolar diffusion. The results are in agreement with a numerical solution of the diffusion equations and with a physical analysis of the luminescence intensity at the centre of the image, which permits the determination of the ambipolar diffusion constant as a function of electron concentration.

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Daniel Paget, Fabian Cadiz, Alistair Rowe, Francois Moreau, Steve Arscott, Emilien Peytavit. 2012-01-12. Imaging ambipolar diffusion of photocarriers in GaAs thin films. https://doi.org/10.1063/1.4730396

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