Suppression of Q-switching instabilities in a passively mode-locked Nd:Y3Al5O12 ceramic laser

We report on continuous wave passive mode-locking laser oscillation in a wide pump power range from a Nd:Y3Al5O12 (Nd:YAG) ceramic. Q-switching instabilities were avoided by means of a proper choose of laser cavity length, neodymium concentration and modulation depth of the saturable absorber mirror. Under optimum conditions, continuous wave mode-locking was obtained for pump powers above 0.4 W. For the maximum absorbed pump power of 3 W average output powers close to 0.75 W with a repetition rate of 52 MHz were obtained.