Quasi-cw diode-pumped Nd:GdVO4 laser passively Q-switched and mode-locked by Cr4+:YAG saturable absorber

We report on the passively Q-switched mode-locking of a quasi-cw (QCW) diode pumped Nd:GdVO4 laser with Cr4+:YAG saturable absorber. We show that by using the QCW pumping high quality Q-switched mode-locking can be easily obtained in the laser even with a simple two-mirror laser cavity configuration. Mode locked pulses with pulse width of about 1 ps at repetition rate variable from 500 MHz to 1 GHz has been obtained.