We report on experimental multi-photon spectroscopy of a hybrid quantum system consisting of a superconducting phase qubit coherently coupled to an intrinsic two-level defect. We directly probe hybridized states of the combined qubit-defect system in the strongly interacting regime, where both the qubit-defect coupling and the driving cannot be considered as weak perturbations. This regime is described by a theoretical model which incorporates anharmonic corrections, multi-photon processes and decoherence. We present a detailed comparison between experiment and theory and find excellent agreement over a wide range of parameters.
@article{arxiv.1005.0773,
title = {Multi-photon spectroscopy of a hybrid quantum system},
author = {Pavel Bushev and Clemens Müller and Jürgen Lisenfeld and Jared H. Cole and Alexander Lukashenko and Alexander Shnirman and Alexey V. Ustinov},
journal= {arXiv preprint arXiv:1005.0773},
year = {2010}
}