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arXiv · 1007.0833

Imaging charge and spin diffusion of minority carriers in GaAs

I. Favorskiy·D. Vu·E. Peytavit·S. Arscott·D. Paget·A. C. H. Rowe
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Abstract

Room temperature electronic diffusion is studied in 3 mum thick epitaxial p+ GaAs lift-off films using a novel circularly polarized photoluminescence microscope. The method is equivalent to using a standard optical microscope and provides a contactless means to measure charge (L) and spin (L_s) diffusion lengths. The measured values of L and L_s are in excellent agreement with the spatially averaged polarization and a sharp reduction in these two quantities (L from 21.3 mum to 1.2 mum and L_s from 1.3 mum to 0.8 mum) is measured with increasing surface recombination. Outwards diffusion results in a factor of 10 increase in the polarization at the excitation spot.

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I. Favorskiy, D. Vu, E. Peytavit, S. Arscott, D. Paget, A. C. H. Rowe. 2010-07-06. Imaging charge and spin diffusion of minority carriers in GaAs. https://doi.org/10.1063/1.3493047

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