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arXiv · 1707.05217

Toward high-fidelity coherent electron spin transport in a GaAs double quantum dot

Xinyu Zhao·Xuedong Hu
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Abstract

In this paper, we investigate how to achieve high-fidelity electron spin transport in a GaAs double quantum dot. Our study examines spin transport from multiple perspectives. We first study how a double dot potential may affect/accelerate spin relaxation. We calculate spin relaxation rate in a wide range of experimental parameters and focus on the occurrence of spin hot spots. A safe parameter regime is identified in order to avoid these spin hot spots. We also study the non-adiabatic transitions in the Landau-Zener process of sweeping the interdot detuning, and propose a scheme to take advantage of possible Landau-Zener-Stükelburg interference to achieve high-fidelity spin transport at a higher speed. Finally, we calculate the double-dot correction on the effective $g$-factor for the tunneling electron, and estimate the resulting phase error between different spin states. Our results should provide a useful guidance for future experiments on coherent electron spin transport.

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Xinyu Zhao, Xuedong Hu. 2017-07-17. Toward high-fidelity coherent electron spin transport in a GaAs double quantum dot. https://arxiv.org/abs/1707.05217

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