Abstract

In recent years, a new discovery in research on multiphoton ionization of atoms - peaks generated by short intense pulses - has attracted substantial attention.^[1-5] While two major groups have made extensive contributions on the experimental side, there has been a relative dearth of theoretical results. The purpose of this paper is to remedy this situation somewhat by presenting detailed calculations (nonperturbative in the active states) of the two-photon ionization of cesium by short pulses. We have chosen to start with this problem, rather than the sevenphoton ionization of xenon actually studied experimentally, since it is simpler structurally and because we are able to accurately determine atomic parameters (dipole matrix elements and Stark shifts) via the quantum defect method. In later work, we plan to apply the same approach to the dynamics of the rare-gas problem by replacing the actual bound-bound coupling by an effective operator, although this will entail a loss of accuracy.

© 1992 IQEC