Coherent and Incoherent Effects in Laser-Induced Autoionization

Abstract

Study of the autoionizing states of the atom and their interaction with the radiation field is becoming increasingly important both from the theoretical and the applied point of view. On the applied side it provides a possible way of producing VUV radiation1–3 and thus under suitable pumping conditions, laser action in VUV, using the autoionizing states, is possible. The interaction also results in very interesting fundamental physical effects,4 which again could lead to the very efficient VUV devices. Normally the interaction of the autoionizing states5 with laser fields is studied by ignoring all incoherent effects. However, one would expect that any source of incoherence such as spontaneous emission, recombination of electrons and ions, collisions, etc., would affect all the basic phenomena that can arise in the interaction of autoionizing states with fields, particularly if resonances are involved. We have undertaken a systematic study of some of the incoherent effects in laser-induced autoionization. I will primarily deal with the effects of spontaneous emission and recombination. This lecture is based on the work carried out with several physicists — S. Haan, K. Burnett, J. Cooper, D. Agassi and P. Anantha Lakshmi.