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Dephasing of qubits by transverse low-frequency noise

Yuriy Makhlin·Alexander Shnirman
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Abstract

We analyze the dissipative dynamics of a two-level quantum system subject to low-frequency, e.g. 1/f noise, motivated by recent experiments with superconducting quantum circuits. We show that the effect of transverse linear coupling of the system to low-frequency noise is equivalent to that of quadratic longitudinal coupling. We further find the decay law of quantum coherent oscillations under the influence of both low- and high-frequency fluctuations, in particular, for the case of comparable rates of relaxation and pure dephasing.

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Yuriy Makhlin, Alexander Shnirman. 2003-12-22. Dephasing of qubits by transverse low-frequency noise. https://doi.org/10.1134/1.1637702

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