Journal of the Optical Society of America B
Theoretical aspects of three-photon two-color ionization of xenon through ac-Stark-shifted resonant Rydberg states
Anne L’Huillier, X. Tang, P. Lambropoulos, Louis A. Lompre, Didier Normand
Abstract
We present a theoretical analysis of a recent experiment [ J. Opt. Soc. Am. B6, 1513 ( 1989)] on two-color three-photon ionization of Xe through resonant even-parity Rydberg states. We calculate second-order ac-Stark shifts, two-photon Rabi frequencies, and ionization widths by using wave functions obtained from a multichannel quantum-defect-theory analysis of the Rydberg series in Xe. We perform a detailed description of the experiment, using the density-matrix formalism, accounting for the temporal and spatial distributions of the laser fields. The agreement with the experiment is good except for the ac-Stark shift of the Rydberg states, which, in our calculation is close to the ponderomotive energy, whereas in the experiment it is measured to be half of this value.