Output characteristics of a passively Q-switched diode-laser pumped ceramic Nd:YAG laser

Abstract

A passively Q-switched diode-laser pumped ceramic Nd:YAG laser has been constructed and the output characteristics has been investigated. The output efficiency of 36.1 % has been obtained with 1.1 at.% of neodymium concentration in the ceramic YAG. For the case of neodymium concentration of 2.0 at.%, the output power decreases as the pump power increases over 6 W. The output power has rapidly decreased more than 10 W of pumping, and the laser output has finally disappeared at pumping power of 13 W. This phenomenon can be explained by the thermal lens effect in the laser material. Passive Q-switching has been carried out using a Cr:YAG crystal in the resonator. The pulse width is 61.2 ns and the repetition rate is 10.1 kHz at the pump power of 1 W. The beam propagation factor M² has been measured to be 1.2, which shows good beam quality of the Q-switched pulse.