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Dephasing of solid-state qubits at optimal points

Yuriy Makhlin·Alexander Shnirman
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Abstract

Motivated by recent experiments with Josephson-junction circuits, we analyze the influence of various noise sources on the dynamics of two-level systems at optimal operation points where the linear coupling to low-frequency fluctuations is suppressed. We study the decoherence due to nonlinear (quadratic) coupling, focusing on the experimentally relevant 1/f and Ohmic noise power spectra. For 1/f noise strong higher-order effects influence the evolution.

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Yuriy Makhlin, Alexander Shnirman. 2003-12-22. Dephasing of solid-state qubits at optimal points. https://doi.org/10.1103/physrevlett.92.178301

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