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Sideband Transitions and Two-Tone Spectroscopy of a Superconducting Qubit Strongly Coupled to an On-Chip Cavity

A. Wallraff·D. I. Schuster·A. Blais·J. M. Gambetta·J. Schreier·L. Frunzio·M. H. Devoret·S. M. Girvin·R. J. Schoelkopf
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Abstract

Sideband transitions are spectroscopically probed in a system consisting of a Cooper pair box strongly but non-resonantly coupled to a superconducting transmission line resonator. When the Cooper pair box is operated at the optimal charge bias point the symmetry of the hamiltonian requires a two photon process to access sidebands. The observed large dispersive ac-Stark shifts in the sideband transitions induced by the strong non-resonant drives agree well with our theoretical predictions. Sideband transitions are important in realizing qubit-photon and qubit-qubit entanglement in the circuit quantum electrodynamics architecture for quantum information processing.

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A. Wallraff, D. I. Schuster, A. Blais, J. M. Gambetta, J. Schreier, L. Frunzio, M. H. Devoret, S. M. Girvin, R. J. Schoelkopf. 2007-03-23. Sideband Transitions and Two-Tone Spectroscopy of a Superconducting Qubit Strongly Coupled to an On-Chip Cavity. https://doi.org/10.1103/physrevlett.99.050501

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