Fast reset and suppressing spontaneous emission of a superconducting qubit

@article{Reed2010FastRA,
  title={Fast reset and suppressing spontaneous emission of a superconducting qubit},
  author={Matthew D. Reed and B. R. Johnson and Andrew A. Houck and Leonardo DiCarlo and Jerry M. Chow and David I. Schuster and Luigi Frunzio and Robert J. Schoelkopf},
  journal={Applied Physics Letters},
  year={2010},
  volume={96},
  pages={203110}
}
Spontaneous emission through a coupled cavity can be a significant decay channel for qubits in circuit quantum electrodynamics. We present a circuit design that effectively eliminates spontaneous emission due to the Purcell effect while maintaining strong coupling to a low-Q cavity. Excellent agreement over a wide range in frequency is found between measured qubit relaxation times and the predictions of a circuit model. Using fast (nanosecond time-scale) flux biasing of the qubit, we… 

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