Compact high stable passively Q-switched Nd:YVO4 laser with Cr4+:YAG

Abstract Compact high stable diode-pumped passively Q-switched Nd:YVO 4 laser was demonstrated via a gradient index lens as an optical pump coupler. Using Cr 4+ :YAG wafer as the saturable absorber, high stable Q-switching operation was performed via controlling the temperature of the laser crystal and the transmitance of the output coupler. When the temperature of the laser crystal was controlled at 33 °C, stable pulses were achieved with the single pulse width of 5.56 ns and the repetition rate of 24.38 kHz. The single pulse energy was about 5.70 μJ, corresponding to a maximum peak power of 1.025 kW.