Mode locking of a Nd:YAlO/sub 3/ laser at 1.08 and 1.34 mu m wavelengths using a single LiIO/sub 3/ crystal

Passive mode locking of a Nd:YAlO/sub 3/ laser at 1.08 and 1.34 mu m using a nonlinear mirror based on second harmonic generation is described. A single 30 degrees cut frequency-doubling LiIO/sub 3/ crystal was used to mode lock both transitions, demonstrating the superiority of this mode-locking technique over that using saturable absorbers. Pulses as short as 50 ps at 1.08 mu m and 15 ps at 1.34 mu m were obtained. A comparative analysis of the mode-locking performance at the two fundamental wavelengths is presented, indicating that the longer pulse duration at 1.08 mu m is due to the higher gain and an insufficient number of round-trips in the pulse train development.