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arXiv · 1008.4755

Optical orientation and spin-dependent recombination in GaAsN alloys under continuous-wave pumping

E. L. Ivchenko·V. K. Kalevich·A. Yu. Shiryaev·M. M. Afanasiev·Y. Masumoto
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Abstract

We present a systematic theoretical study of spin-dependent recombination and its effect on optical orientation of photoelectron spins in semiconductors with deep paramagnetic centers. For this aim we generalize the Shockley-Read theory of recombination of electrons and holes through the deep centers with allowance for optically-induced spin polarization of free and bound electrons. Starting from consideration of defects with three charge states we turn to the two-charge-state model possessing nine parameters and show that it is compatible with available experimental data on undoped GaAsN alloys. In the weak- and strong-pumping limits, we derive simple analytic equations which are useful in prediction and interpretation of experimental results. Experimental and theoretical dependencies of the spin-dependent-recombination ratio and degree of photoluminescence circular polarization on the pumping intensity and the transverse magnetic field are compared and discussed.

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E. L. Ivchenko, V. K. Kalevich, A. Yu. Shiryaev, M. M. Afanasiev, Y. Masumoto. 2010-08-27. Optical orientation and spin-dependent recombination in GaAsN alloys under continuous-wave pumping. https://doi.org/10.1088/0953-8984%2F22%2F46%2F465804

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