Prediction and retrodiction for a continuously monitored superconducting qubit.

  title={Prediction and retrodiction for a continuously monitored superconducting qubit.},
  author={Dian Tan and Steven J. Weber and Irfan Siddiqi and Klaus M{\o}lmer and Kater W. Murch},
  journal={Physical review letters},
  volume={114 9},
The quantum state of a superconducting transmon qubit inside a three-dimensional cavity is monitored by transmission of a microwave field through the cavity. The information inferred from the measurement record is incorporated in a density matrix ρ_{t}, which is conditioned on probe results until t, and in an auxiliary matrix E_{t}, which is conditioned on probe results obtained after t. Here, we obtain these matrices from experimental data and we illustrate their application to predict and… 

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