Efficient Diode-Pumped Passively Q-Switched Nd:GdVO₄ Lasers

An efficient diode-pumped Nd:GdVO₄ laser passively Q-switched by a Cr⁴⁺:YAG as an saturable absorber was developed. A KTP crystal is used for the extra-cavity second-harmonic generation (SHG) and a BBO crystal for the sum frequency mixing (SFM). The green output power is 172 mW at incident pump power of 8 W. The ultraviolet (UV) output power is measured to be 20 mW at the same pump power. The peak power of UV laser is 143 W with the pulse repetition rate of 14 kHz and pulse width of 10 ns.