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 4x10 to the 4th times over the cw level.