Crossover from weak to strong coupling regime in dispersive circuit QED

I. Serban; E. Solano; F. K. Wilhelm

doi:10.1209/0295-5075/80/40011

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Crossover from weak to strong coupling regime in dispersive circuit QED

I. Serban·E. Solano·F. K. Wilhelm

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Abstract

We study the decoherence of a superconducting qubit due to the dispersive coupling to a damped harmonic oscillator. We go beyond the weak qubit-oscillator coupling, which we associate with a phase Purcell effect, and enter into a strong coupling regime, with qualitatively different behavior of the dephasing rate. We identify and give a physicaly intuitive discussion of both decoherence mechanisms. Our results can be applied, with small adaptations, to a large variety of other physical systems, e. g. trapped ions and cavity QED, boosting theoretical and experimental decoherence studies.

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I. Serban, E. Solano, F. K. Wilhelm. 2007-10-30. Crossover from weak to strong coupling regime in dispersive circuit QED. https://doi.org/10.1209/0295-5075%2F80%2F40011

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