Thermal excitation of multi-photon dressed states in circuit quantum electrodynamics
J. M. Fink, Matthias Baur, R. Bianchetti, Stefan Filipp, M. Göppl, Peter Leek, L. Steffen, Alexandre Blais, Andreas J. Wallraff · Physica Scripta · 2009
The exceptionally strong coupling realizable between superconducting qubits and photons stored in an on-chip microwave resonator allows for the detailed study of matter–light interactions in the realm of circuit quantum electrodynamics (QED). Here we investigate the resonant interaction between a single transmon-type multilevel artificial atom and weak thermal and coherent fields. We explore up to three photon dressed states of the coupled system in a linear response heterodyne transmission measurement. The results are in good quantitative agreement with a generalized Jaynes–Cummings model. Our data indicate that the role of thermal fields in resonant cavity QED can be studied in detail using superconducting circuits.