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arXiv · 1902.09515

Phonon-assisted carrier tunneling in coupled quantum dot systems with hyperfine-induced spin flip

Paweł Karwat·Krzysztof Gawarecki·Paweł Machnikowski
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Abstract

We calculate the rates of phonon-assisted hyperfine spin flips during electron and hole tunneling between quantum dots in a self-assembled quantum dot molecule. We show that the hyperfine process dominates over the spin-orbit-induced spin relaxation in magnetic fields up to a few Tesla for electrons, while for holes this cross-over takes place at field magnitudes of a fraction of Tesla, upon the assumption of a large $d$-shell admixture to the valence band state, resulting in a strong transverse hyperfine coupling. The interplay of the two spin-flip mechanisms leads to a minimum of the spin-flip probability, which is in principle experimentally measurable and can be used as a test for the presence of substantial transverse hyperfine couplings in the valence band.

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Paweł Karwat, Krzysztof Gawarecki, Paweł Machnikowski. 2019-02-25. Phonon-assisted carrier tunneling in coupled quantum dot systems with hyperfine-induced spin flip. https://doi.org/10.1103/physrevb.104.045308

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