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Dephasing of Josephson qubits close to optimal points

S. V. Syzranov·Yu. Makhlin
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Abstract

Decoherence of Josephson qubits can be substantially reduced by tuning their parameters to optimal operation points, with only quadratic coupling to fluctuations. We analyze dephasing due to 1/f noise for a two-level system, detuned from an optimal point, i.e., the crossover to the linear-coupling regime, both for free induction decay and for spin-echo experiments. Influence of several noise sources is also discussed.

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S. V. Syzranov, Yu. Makhlin. 2005-12-29. Dephasing of Josephson qubits close to optimal points. https://arxiv.org/abs/cond-mat/0512701

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