4 research outputs found
Time-resolved qubit readout via nonlinear Josephson inductance
19 pĂĄginas, 3 figuras.We propose a generalization of dispersive qubit readout that
provides the time evolution of a flux qubit observable. Our proposal relies on
the nonlinear coupling of the qubit to a harmonic oscillator with high frequency,
representing a dc superconducting quantum interference device. Information
about the qubit dynamics is obtained by recording the oscillator response to
resonant driving and subsequent lock-in detection. The measurement process is
simulated for the example of coherent qubit oscillations. This corroborates the
underlying measurement relation and also reveals that the measurement scheme
possesses low backaction and high fidelity.This work was supported by the German Research Foundation (DFG) through
the Collaborative Research Centre SFB 631 and through the German Excellence Initiative via
the âNanosystems Initiative Munich (NIM)â. We also acknowledge support from the Spanish
Ministry of Science and Innovation (MICINN) through grant numbers MAT2008/02626 (SK),
FIS2008-01240 and FIS2009-13364-C02-0 (DZ).Peer reviewe