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arXiv · 2002.03195

Hole spin-flip transitions in a self-assembled quantum dot

Mateusz Krzykowski·Krzysztof Gawarecki·Pawel Machnikowski
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Abstract

In this work, we investigate hole spin-flip transitions in a single self-assembled InGaAs/GaAs quantum dot. We find the hole wave functions using the 8-band $kp$ model and calculate phonon-assisted spin relaxation rates for the ground-state Zeeman doublet. We systematically study the importance of various admixture- and direct spin-phonon mechanisms giving rise to the transition rates. We show that the biaxial and shear strain constitute dominant spin-admixture coupling mechanisms. Then, we demonstrate that hole spin lifetime can be increased if a quantum dot is covered by a strain-reducing layer. Finally, we show that the spin relaxation can be described by an effective model.

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Mateusz Krzykowski, Krzysztof Gawarecki, Pawel Machnikowski. 2020-02-08. Hole spin-flip transitions in a self-assembled quantum dot. https://doi.org/10.1103/physrevb.102.205301

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