Bang-Bang refocusing of a qubit exposed to telegraph noise

H. Gutmann; F. K. Wilhelm; W. M. Kaminsky; S. Lloyd

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Bang-Bang refocusing of a qubit exposed to telegraph noise

H. Gutmann·F. K. Wilhelm·W. M. Kaminsky·S. Lloyd

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Abstract

We investigate the decoherence effect of telegraph noise on a single qubit, usually provoked by bistable fluctuators. To diminish the dephasing and relaxation impact an effective refocusing scheme (so-called Bang-Bang pulses) is proposed. Detailed numerical as well as analytical random walk analysis allows in particular to evaluate the applicability of non-perfect Bang-Bang pulses.

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H. Gutmann, F. K. Wilhelm, W. M. Kaminsky, S. Lloyd. 2004-12-16. Bang-Bang refocusing of a qubit exposed to telegraph noise. https://arxiv.org/abs/cond-mat/0412452

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