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arXiv · cond-mat/0512578

Decoherence from ensembles of two-level fluctuators

Josef Schriefl·Yuriy Makhlin·Alexander Shnirman·Gerd Schön
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Abstract

1/f noise, the major source of dephasing in Josephson qubits, may be produced by an ensemble of two-level systems. Depending on the statistical properties of their distribution, the noise distribution can be Gaussian or non-Gaussian. The latter situation is realized, for instance, when the distribution of coupling strengths has a slowly decaying power-law tail. In this regime questions of self-averaging and sample-to-sample fluctuations become crucial. We study the dephasing process for a class of distribution functions and analyze the self-averaging properties of the results.

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Josef Schriefl, Yuriy Makhlin, Alexander Shnirman, Gerd Schön. 2005-12-22. Decoherence from ensembles of two-level fluctuators. https://doi.org/10.1088/1367-2630%2F8%2F1%2F001

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