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arXiv · 1905.07947

Spin dynamics of hot excitons in diluted magnetic semiconductors with spin-orbit interaction

Florian Ungar·Pablo Ignacio Tamborenea·Vollrath Martin Axt
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Abstract

We explore the impact of a Rashba-type spin-orbit interaction in the conduction band on the spin dynamics of hot excitons in diluted magnetic semiconductor quantum wells. In materials with strong spin-orbit coupling, we identify parameter regimes where spin-orbit effects greatly accelerate the spin decay and even change the dynamics qualitatively in the form of damped oscillations. Furthermore, we show that the application of a small external magnetic field can be used to either mitigate the influence of spin-orbit coupling or entirely remove its effects for fields above a material-dependent threshold.

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Florian Ungar, Pablo Ignacio Tamborenea, Vollrath Martin Axt. 2019-07-29. Spin dynamics of hot excitons in diluted magnetic semiconductors with spin-orbit interaction. https://doi.org/10.1103/physrevb.100.045306

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