SOLID-STATE LOW-LOSS INTRACAVITY SATURABLE ABSORBER FOR ND-YLF LASERS - AN ANTIRESONANT SEMICONDUCTOR FABRY-PEROT SATURABLE ABSORBER

We introduce a new low-loss fast intracavity semiconductor Fabry-Perot saturable absorber operated at antiresonance both to start and sustain stable mode locking of a cw-pumped Nd:YLF laser. We achieved a 3.3-ps pulse duration at a 220-MHz repetition rate. The average output power was 700 mW with 2 W of cw pump power from a Ti:sapphire laser. At pump powers of less than 1.6 W the laser self-Q switches and produces 4-ps pulses within a 1.4-mu-s Q-switched pulse at an almost-equal-to 150-kHz repetition rate determined by the relaxation oscillation of the Nd:YLF laser. Both modes of operation are stable. In terms of coupled-cavity mode locking, the intracavity antiresonant Fabry-Perot saturable absorber corresponds to monolithic resonant passive mode locking.