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A nonlinear mechanism of charge qubit decoherence in a lossy cavity: the quasi normal mode approach

Y. B. Gao·Y. D. Wang·C. P. Sun
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Abstract

In the viewpoint of quasi normal modes, we describe a novel decoherence mechanism of charge qubit of Josephson Junctions (JJ) in a lossy micro-cavity, which can appear in the realistic experiment for quantum computation based on JJ qubit. We show that the nonlinear coupling of a charge qubit to quantum cavity field can result in an additional dissipation of resonant mode due to its effective interaction between those non-resonant modes and a resonant mode, which is induced by the charge qubit itself. We calculate the characterized time of the novel decoherence by making use of the system plus bath method.

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Y. B. Gao, Y. D. Wang, C. P. Sun. 2004-12-21. A nonlinear mechanism of charge qubit decoherence in a lossy cavity: the quasi normal mode approach. https://doi.org/10.1103/physreva.71.032302

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