Direct comparison of the thermal lenses of diode-end-pumped Nd:YVO4 and Nd:GdVO4 lasers using a simple evaluation technique

Abstract

In this work, the thermal lenses generated in diode-end-pumped Nd:YVO4 and Nd:GdVO4 lasers were evaluated and compared using a simple technique based on the stability criteria of a plane-parallel laser resonator [example 1], as shown in the top figure. The general stability parameters still hold for this resonator with a thin thermal lens close to the end-mirror of the cavity [2]. By increasing the pump power into the laser crystal, the resonator will become unstable when the thermal lens length is equal to the fixed length L2, at the point where the stability criterion 0<g1g2<1 no longer holds