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arXiv · 1208.1284

Spin Qubit Relaxation in a Moving Quantum Dot

Peihao Huang·Xuedong Hu
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Abstract

Long-range quantum communication for spin qubits is an important open problem. Here we study decoherence of an electron spin qubit that is being transported in a moving quantum dot. We focus on spin decoherence due to spin-orbit interaction and a random electric potential. We find that at the lowest order, the motion induces longitudinal spin relaxation, with a rate linear in the dot velocity. Our calculated spin relaxation time ranges from sub $\mu$s in GaAs to above ms in Si, making this relaxation a significant decoherence channel. Our results also give clear indications on how to reduce the decoherence effect of electron motion.

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Peihao Huang, Xuedong Hu. 2012-08-06. Spin Qubit Relaxation in a Moving Quantum Dot. https://doi.org/10.1103/physrevb.88.075301

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