Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 79: Superconductivity: Superconducting Electronics - Circuit QED
TT 79.1: Vortrag
Donnerstag, 15. März 2018, 09:30–09:45, H 2053
Anharmonic quantum oscillator under field drive: probing the AC Stark shift of higher levels — •Martin Weides1,2, Andre Schneider1, Patrizia Stehle1, Jochen Braumueller1, Hannes Rotzinger1, Lingzhen Guo3, Michael Marthaler3, and Alexey Ustinov1 — 1Institute of Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany — 2Materials Science in Mainz, University Mainz, Germany — 3Institute for Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
We report on the investigation of a superconducting anharmonic multi-level circuit under the influence of a detuned and strong microwave drive. The AC Stark shift of higher level transition frequencies caused by the applied drive is investigated. We demonstrate that this shift depends on the anharmonicity, the drive amplitude and the detuning between drive and transition frequency. For large detunings we find the shift to be linear to the power of the drive. Experimentally, multi-photon transitions via virtual energy levels of our system up to the third excited state are observed. The measured AC Stark shift of higher order multi-photon transitions under increasing drive amplitude is demonstrated to be in good agreement with the analytic model and numerical simulations. Having a detailed model of the qudit behavior, we can take the qudit as a sensor for high excitation numbers in coupled harmonic systems like microwave resonators or magnonic systems by observing the shift of the qudit levels.