Qubit measurement error from coupling with a detuned neighbor in circuit QED

  title={Qubit measurement error from coupling with a detuned neighbor in circuit QED},
  author={Mostafa Khezri and Justin Dressel and Alexander N. Korotkov},
  journal={Physical Review A},
© 2015 American Physical Society. In modern circuit QED architectures, superconducting transmon qubits are measured via the state-dependent phase and amplitude shift of a microwave field leaking from a coupled resonator. Determining this shift requires integrating the field quadratures for a nonzero duration, which can permit unwanted concurrent evolution. Here we investigate such dynamical degradation of the measurement fidelity caused by a detuned neighboring qubit. We find that in realistic… Expand
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