Influence of External Fields and Environment on the Dynamics of Phase Qubit-Resonator System

Abstract

We analyze the dynamics of a qubit-resonator system coupled with a thermal bath and external electromagnetic fields. Using the evolution equations for the set of Heisenberg operators, that describe the whole system, we derive an expression for the resonator field, accounting for the resonator-drive,-bath, and -qubit interaction. The renormalization of the resonator frequency, caused by the qubit-resonator interaction, is accounted for. Using solutions for the resonator field, we derive the equation describing qubit dynamics. The influence of the qubit evolution during the measurement time on the fidelity of a single-shot measurement is studied. The relation between the fidelity and measurement time is shown explicitly. Also, an expression describing relaxation of the superposition qubit state towards its stationary value is derived. The possibility of controlling this state, by varying the amplitude and frequency of drive, is shown.

15 pages

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Cited by in corpus (4)

• Few-photon Fock-state wave packet interacting with a cavity-atom system in a waveguide: Exact quantum state dynamics
• Single-photon limit of dispersive readout of a qubit with a photodetector
• Optimal conditions for high-fidelity dispersive readout of a qubit with a photon-number-resolving detector
• Transitional dynamics of a phase qubit-resonator system: requirements for fast readout of a phase qubit