Quantum Bayesian approach to circuit QED measurement
نویسنده
چکیده
We present a simple formalism describing evolution of a qubit in the process of its measurement in a circuit QED setup. When a phase-sensitive amplifier is used, the evolution depends on only one output quadrature, and the formalism is the same as for a broadband setup. When a phasepreserving amplifier is used, the qubit evolution depends on two output quadratures. In both cases a perfect monitoring of the qubit state and therefore a perfect quantum feedback is possible.
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