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arXiv · 0707.4040

Leakage-induced decoherence during single electron spin manipulation in a double quantum dot

Shi-Hua Ouyang·Chi-Hang Lam·J. Q. You
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Abstract

Coherent single electron spin oscillation in a double quantum dot system driven by a magnetic electron spin resonance field is studied theoretically using a Bloch-type rate equation approach. The oscillation frequency and relaxation time obtained using typical model parameters are consistent with experiment findings. The dominant decoherence mechanism is identified to be a leakage current through a Coulomb blockade barrier at a quantum dot during the spin manipulation. Nuclear field fluctuations which induce a long relaxation time are found to contribute only negligibly to the decoherence despite an earlier suggestion.

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Shi-Hua Ouyang, Chi-Hang Lam, J. Q. You. 2007-07-27. Leakage-induced decoherence during single electron spin manipulation in a double quantum dot. https://arxiv.org/abs/0707.4040

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