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Spin-dependent electron dynamics and recombination in GaAs(1-x)N(x) alloys at room temperature

V. K. Kalevich·A. Yu. Shiryaev·E. L. Ivchenko·A. Yu. Egorov·L. Lombez·D. Lagarde·X. Marie·T. Amand
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Abstract

We report on both experimental and theoretical study of conduction-electron spin polarization dynamics achieved by pulsed optical pumping at room temperature in GaAs(1-x)N(x) alloys with a small nitrogen content (x = 2.1, 2.7, 3.4%). It is found that the photoluminescence circular polarization determined by the mean spin of free electrons reaches 40-45% and this giant value persists within 2 ns. Simultaneously, the total free-electron spin decays rapidly with the characteristic time ~150 ps. The results are explained by spin-dependent capture of free conduction electrons on deep paramagnetic centers resulting in dynamical polarization of bound electrons. We have developed a nonlinear theory of spin dynamics in the coupled system of spin-polarized free and localized carriers which describes the experimental dependencies, in particular, electron spin quantum beats observed in a transverse magnetic field.

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V. K. Kalevich, A. Yu. Shiryaev, E. L. Ivchenko, A. Yu. Egorov, L. Lombez, D. Lagarde, X. Marie, T. Amand. 2006-12-27. Spin-dependent electron dynamics and recombination in GaAs(1-x)N(x) alloys at room temperature. https://doi.org/10.1134/s0021364007030095

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