New analysis of KrF picosecond pulse experiment

摘要

A new model for analyzing the behavior of the KrF laser medium in response to a short ((approximately) 1 ps) saturating pulse is presented. For pulse durations much less than the mean collision time, the orientation of the KrF angular momentum vector, J, is fixed in space and the rotational M levels are inherently unmixed. The usual assumption of a single stimulated emission cross section, is replaced by one which includes a distribution of cross sections (and populations) which arise from the projection of the dipole along the laser polarization axis. We find that a simple, Franz-Nodvik analysis, using a single saturation fluence parameter, is inaccurate in the short pulse regime.