Effects of the Relative Phase and Pulse Delay of Laser Fields on Atomic Systems Involving Continua.

We study how laser-atom interactions are affected by the relative phase and pulse-delay of laser fields. Atomic systems are described for both cases in terms of the time -dependent density matrix equations. By using simple models, we find that significant phase effects are obtained for atomic systems involving a smooth continuum as well as a structured one, which implies the presence of autoionizing states. In addition to simple models, our theory is also applied to much a more complex situation in Xe, involving many channels, where we find again profound phase effects. Effects of the laser pulse-delay are also discussed in terms of atomic population transfer and the generation of the four-wave mixing. We find that pulse-delay can help the efficient population transfer as well as wave -mixing processes. (Copies available exclusively from Micrographics Department, Doheny Library, USC, Los Angeles, CA 90089 -0192.).