Theory of weak continuous measurements in a strongly driven quantum bit

  title={Theory of weak continuous measurements in a strongly driven quantum bit},
  author={A. Yu. Smirnov},
  journal={Physical Review B},
  • A. Smirnov
  • Published 2 June 2003
  • Physics
  • Physical Review B
Continuous spectroscopic measurements of a strongly driven superconducting qubit by means of a high-quality tank circuit (a linear detector) are under study. Output functions of the detector\char22{}namely, a spectrum of voltage fluctuations and an impedance\char22{}are expressed in terms of the qubit spectrum and magnetic susceptibility. The nonequilibrium spectrum of the current fluctuations in the qubit loop and the linear response function of the driven qubit coupled to a heat bath are… 
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