Abstract

The past decade has seen an enormous effort devoted to studies of multiphoton ionization by very strong radiation fields. To generate the power required by experiments in this area, they must be performed with pulsed lasers. However, since it is simpler to construct theories which treat the light intensity as constant or slowly varying, cw theories are the rule. They give a rather good account of observations for pulses of rather long duration. Recently, however, Freeman et al.¹ and Agostini et al.^2,3 have reported the appearance of an interesting new structure in a photoelectron structure for ionization produced by very short pulses.

© 1990 Optical Society of America