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arXiv · 1104.1111

Hyperfine interaction dominated dynamics of nuclear spins in self-assembled quantum dots

Christian Latta·Ajit Srivastava·Atac Imamoglu
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Abstract

We measure the dynamics of nuclear spins in a self-assembled quantum dot at a magnetic field of 5 Tesla and identify two distinct mechanisms responsible for the decay of the Overhauser field. We attribute a temperature-independent decay which lasts ~100 seconds to intra-dot diffusion induced by hyperfine-mediated indirect nuclear spin interaction. In addition, we observe a gate-voltage and temperature dependent decay stemming from co-tunneling mediated nuclear spin flip processes. By adjusting the gate-voltage and lowering the electron temperature to ~200 milliKelvin, we prolong the corresponding decay time to ~30 hours. Our measurements indicate possibilities for exploring quantum dynamics of the central spin model using a single self-assembled quantum dot.

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Christian Latta, Ajit Srivastava, Atac Imamoglu. 2011-04-06. Hyperfine interaction dominated dynamics of nuclear spins in self-assembled quantum dots. https://doi.org/10.1103/physrevlett.107.167401

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