Ionization of barium through a coherent excitation of two bound intermediate states
Laboratoire Aimé Cotton, CNRS II, bâtiment 505, 91405 Orsay Cedex, France
2 Atomic and Molecular Physics Laboratory, Physics Department, University of Ioannina, 45110 Ioannina, Greece
Published online: 15 May 2000
We have investigated theoretically the asymmetrical photoionization yields into the , and continuum channels of atomic barium observed by Wang, Chen and Elliott [Phys. Rev. Lett. 77, 2416 (1996)] in the study of coherent control through two-color resonant interfering paths. The atomic parameters obtained from a theoretical approach based on a combination of jj-coupled eigenchannel R-matrix and Multichannel Quantum Defect Theory are used to analyze the photoionization spectra from the and 6s7p states with polarized light beams. The studied energy range includes the 6p7p autoionizing resonances. The dynamics of the two-color photoionization is governed by the coherent excitation of the 6s6p and intermediate states. This excitation is described as an adiabatic process in the rotating wave approximation. The influence of the radiative decay, spatial distribution of the intensities of the laser beams and hyperfine interaction is discussed.
PACS: 32.80.Fb – Photoionization of atoms and ions / 32.80.Qk – Coherent control of atomic interactions with photons / 31.15.Ar – Ab initio calculations
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000