Strong-Field Effects in the Rabi Oscillations of the Superconducting Phase Qubit
Frederick W. Strauch, S. K. Dutta, Hanhee Paik, Tauno Palomaki, Kaushik Mitra, Benjamin K. Cooper, Rupert Lewis, J. R. Anderson, Alex J. Dragt, Christopher J. Lobb, F. C. Wellstood · IEEE Transactions on Applied Superconductivity · 2007
Rabi oscillations have been observed in many superconducting devices, and represent prototypical logic operations for quantum bits (qubits) in a quantum computer. We use a three-level multiphoton analysis to understand the behavior of the superconducting phase qubit (current-biased Josephson junction) at high microwave drive power. Analytical and numerical results for the ac Stark shift, single-photon Rabi frequency, and two-photon Rabi frequency are compared to measurements made on a dc SQUID phase qubit with Nb/AlOx/Nb tunnel junctions. Good agreement is found between theory and experiment.