Spontaneous generation of giant pulses in a diode-pumped Nd: YVO4 laser

Spontaneous generation of giant pulses was observed from a diode-pumped Nd: YVO4 laser with a plane-concave resonator by adjusting the cavity length near the hemispherical resonator configuration and misaligning the cavity axis with respect to the pump beam. Self-pulsation occurs because of the beating among near degenerate modes being tuned to resonate with the relaxation oscillation of laser modes. By using a concave mirror of 10-mm radius of curvature, giant pulses were obtained at approximately 10 kHz with pulse widths as short as 2.4 ns corresponding to an increase in the peak power of more than 4 x 10(4) times over the cw level. (C) 2005 Optical Society of America.