Stark effect and generalized Bloch-Siegert shift in a strongly driven two-level system
arXiv:1005.3446 · doi:10.1103/PhysRevLett.105.257003
Abstract
A superconducting qubit was driven in an ultrastrong fashion by an oscillatory microwave field, which was created by coupling via the nonlinear Josephson energy. The observed Stark shifts of the `atomic' levels are so pronounced that corrections even beyond the lowest-order Bloch-Siegert shift are needed to properly explain the measurements. The quasienergies of the dressed two-level system were probed by resonant absorption via a cavity, and the results are in agreement with a calculation based on the Floquet approach.
4+ pages