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arXiv · 2005.05947

Phonon-assisted relaxation between triplet and singlet states in a self-assembled double quantum dot

Krzysztof Gawarecki·Paweł Machnikowski
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Abstract

We study theoretically phonon-induced spin dynamics of two electrons confined in a self-assembled double quantum dot. We calculate the transition rates and time evolution of occupations for the spin-triplet and spin-singlet states. We characterize the relative importance of various relaxation channels as a function of the electric and magnetic fields. The simulations are based on a model combining the eight-band k.p method and configuration-interaction approach. We show that the electron g-factor mismatch between the Zeeman doublets localized on different dots opens a relatively fast triplet-singlet relaxation channel. We also demonstrate, that the relaxation near the triplet-singlet anticrossing is slowed down up to several orders of magnitude due to vanishing of some relaxation channels.

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Krzysztof Gawarecki, Paweł Machnikowski. 2020-05-12. Phonon-assisted relaxation between triplet and singlet states in a self-assembled double quantum dot. https://arxiv.org/abs/2005.05947

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