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Observation of Quantum Oscillations between a Josephson Phase Qubit and a Microscopic Resonator using Fast Readout



Ken Cooper, Matthias Steffen, Robert McDermott, Raymond W. Simmonds, Seongshik Oh, Dustin A. Hite, David P. Pappas, John M. Martinis


We have detected coherent quantum oscillations between Josephson phase qubits and microscopic critical current fluctuators by implementing a new state readout technique that is an order of magnitude faster than previous methods. The period of the oscillations is consistent with the spectroscopic splittings observed in the qubit's resonant frequency. The results point to a possible mechanism for decoherence and reduced measurement fidelity in superconducting qubits, and they demonstrate the means to measure two-qubit interactions in the time domain.
Physical Review Letters


coherent oscillation, fast readout, Josephson junction, phase qubit, quantum computing, qubit, superconductivity
Created October 25, 2004, Updated February 17, 2017