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arXiv · 2212.10683

Spin dynamics in quantum dots on liquid helium

M. I. Dykman·Ofek Asban·Qianfan Chen·Dafei Jin·S. A. Lyon
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Abstract

Liquid He-4 is free from magnetic defects, making it an ideal substrate for electrons with long-lived spin states. Such states can serve as qubit states. Here we consider the spin states of electrons electrostatically localized in quantum dots on a helium surface. Efficient gate operations in this system require spin-orbit coupling. It can be created by a nonuniform magnetic field from a current-carrying wire, can be turned on and off, and allows one to obtain large electro-dipole moment and comparatively fast coupling of spins in neighboring dots. Of central importance is to understand the spin decay due to the spin-orbit coupling. We establish the leading mechanism of such decay and show that the decay is sufficiently slow to enable high-fidelity single- and two-qubit gate operations

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M. I. Dykman, Ofek Asban, Qianfan Chen, Dafei Jin, S. A. Lyon. 2022-12-20. Spin dynamics in quantum dots on liquid helium. https://doi.org/10.1103/physrevb.107.035437

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