Crossover from weak to strong coupling regime in dispersive circuit QED

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.

Published version

References in corpus (5)

• Resolving photon number states in a superconducting circuit
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Cited by in corpus (2)

• Probing the quantum coherence of a nanomechanical resonator using a superconducting qubit: I. Echo scheme
• Stochastic Wave-Function Unravelling of the Generalized Lindblad Master Equation