Abstract

A model for optimization of longitudinally pumped solid-state lasers, in which the pump-beam was described by its M² factor, is proposed. Using the mode-overlap integrals, numerical investigations were carried out to obtain the optimum focusing position and pump beam waist, that ensure a minimum threshold pump power and maximum overlap efficiency, at a defined laser beam spot-size. The numerical data were fitted with analytical functions of pump beam M² factor, active medium absorption coefficient at the pump wavelength and laser beam volume. The experiments were performed with a Nd:YAG laser, longitudinally pumped with a maximum 10W fiber-coupled diode laser system and a Nd:YVO₄ miniature laser, pumped by a max. 1W diode laser. A fairly good agreement with theory was obtained.

© 1998 Optical Society of America