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arXiv · 1107.0810

Selection rules in a strongly coupled qubit-resonator system

T. Niemczyk·F. Deppe·E. P. Menzel·M. J. Schwarz·H. Huebl·F. Hocke·M. Häberlein·M. Danner·E. Hoffmann·A. Baust·E. Solano·J. J. Garcia-Ripoll·A. Marx·R. Gross
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Abstract

Superconducting qubits acting as artificial two-level atoms allow for controlled variation of the symmetry properties which govern the selection rules for single and multiphoton excitation. We spectroscopically analyze a superconducting qubit-resonator system in the strong coupling regime under one- and two-photon driving. Our results provide clear experimental evidence for the controlled transition from an operating point governed by dipolar selection rules to a regime where one- and two-photon excitations of the artificial atom coexist. We find that the vacuum coupling between qubit and resonator can be straightforwardly extracted from the two-photon spectra where the detuned two-photon drive does not populate the relevant resonator mode significantly.

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T. Niemczyk, F. Deppe, E. P. Menzel, M. J. Schwarz, H. Huebl, F. Hocke, M. Häberlein, M. Danner, E. Hoffmann, A. Baust, E. Solano, J. J. Garcia-Ripoll, A. Marx, R. Gross. 2011-07-05. Selection rules in a strongly coupled qubit-resonator system. https://arxiv.org/abs/1107.0810

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