Pulse width compression in a diode-pumped doubly Q-switched YVO4/Nd:YVO4/KTP green laser with EO and Cr4+:YAG

We propose a doubly Q-switched YVO4/Nd:YVO4 green laser by simultaneously employing an electro-optic (EO) modulator and a Cr4+:YAG wafer in a resonator. This device can compress pulse duration significantly when compared with a single EO Q-switched green laser. An output pulse width of 5 ns has been achieved with peak power of 21 kW at 4 kHz. A coupled equation is given to theoretically analyze the experimental results, in which the influences of population-inversion density (PID) on laser character are taken into account and lead to a good agreement with the experimental results.