AUTLER-TOWNES SPLITTING IN AN IONIZATION SCHEME INCLUDING 2 BOUND LEVELS COHERENTLY COUPLED BY BOTH LINEARLY AND CIRCULARLY-POLARIZED LASERS

Photoionization signals are obtained by using the Schrodinger equation for an atomic system interacting simultaneously with linearly and the circularly polarized fields. The ionization schemes chosen have two b ound levels of the total angular momenta of J=0 and 1 and one autoioni zation level of J=0. The bound levels are coherently coupled with the applied fields, and the autoionization level is incoherently coupled. Both double-peak and double-dip structures in the obtained ionization signals can be explained by the effects of Autler-Townes splitting. In particular, the double-dip structure turns out to be due to the effec t of population trapping. Experimentally, the double-dip, as well as t he double-peak, structure in the ionization signal can be used to obta in the cross-section.