Engineering decoherence in Josephson persistent-current qubits

  title={Engineering decoherence in Josephson persistent-current qubits
  author={Caspar H. van der Wal and Frank K. Wilhelm and C. Harmans and Johann E. Mooij},
  journal={The European Physical Journal B - Condensed Matter and Complex Systems},
Abstract:We discuss the relaxation and dephasing rates that result from the control and the measurement setup itself in experiments on Josephson persistent-current qubits. For control and measurement of the qubit state, the qubit is inductively coupled to electromagnetic circuitry. We show how this system can be mapped on the spin-boson model, and how the spectral density of the bosonic bath can be derived from the electromagnetic impedance that is coupled to the qubit. Part of the… 
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