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arXiv · 2106.00044

Dynamic polarization of electron spins in indirect band gap (In,Al)As/AlAs quantum dots in weak magnetic field: experiment and theory

T. S. Shamirzaev·A. V. Shumilin·D. S. Smirnov·J. Rautert·D. R. Yakovlev·M. Bayer
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Abstract

A novel spin orientation mechanism - dynamic electron spin polarization has been recently suggested in Phys. Rev. Lett. $\mathbf{125}$, 156801 (2020). It takes place for unpolarized optical excitation in weak magnetic fields of the order of a few millitesla. In this paper we demonstrate experimentally and theoretically that the dynamic electron spin polarization degree changes sign as a function of time, strength of the applied magnetic field and its direction. The studies are performed on indirect band-gap (In,Al)As/AlAs quantum dots and their results are explained in the framework of a theoretical model developed for our experimental setting.

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T. S. Shamirzaev, A. V. Shumilin, D. S. Smirnov, J. Rautert, D. R. Yakovlev, M. Bayer. 2021-05-31. Dynamic polarization of electron spins in indirect band gap (In,Al)As/AlAs quantum dots in weak magnetic field: experiment and theory. https://doi.org/10.1103/physrevb.104.115405

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