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arXiv · 2208.02037

Nuclear spin diffusion in the central spin system of a GaAs/AlGaAs quantum dot

Peter Millington-Hotze·Santanu Manna·Saimon F. Covre da Silva·Armando Rastelli·Evgeny A. Chekhovich
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Abstract

The spin diffusion concept provides a classical description of a purely quantum-mechanical evolution in inhomogeneously polarized many-body systems such as nuclear spin lattices. The central spin of a localized electron alters nuclear spin diffusion in a way that is still poorly understood. In contrast to previous predictions, we show experimentally that in GaAs/AlGaAs quantum dots the electron spin accelerates nuclear spin diffusion, without forming any Knight field gradient barrier. Such acceleration is present even at high magnetic fields, which we explain as a result of electron spin-flip fluctuations. Diffusion-limited nuclear spin lifetimes range between 1 and 10 s, providing plenty of room for recent proposals seeking to store and process quantum information using quantum dot nuclear spins.

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Peter Millington-Hotze, Santanu Manna, Saimon F. Covre da Silva, Armando Rastelli, Evgeny A. Chekhovich. 2022-08-03. Nuclear spin diffusion in the central spin system of a GaAs/AlGaAs quantum dot. https://doi.org/10.1038/s41467-023-38349-0

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