Compact KTA-based intracavity optical parametric oscillator driven by a passively Q-switched Nd:GdVO4 laser

We present a compact and efficient KTA-based intracavity optical parametric oscillator(IOPO) driven by a diode-end-pumped Nd:GdVO4/Cr:YAG passively Q-switched laser. At the incident diode pump power of 9.2 W, signal (1.53 mu m) and idler (3.47 mu m) average output powers of up to 744 and 356 mW, respectively, have been obtained. The total (signal + idler) optical-to-optical conversion efficiency is as high as 12%. By using the knife-edge method, near-diffraction-limited signal and idler beams have been detected, and the M-2 factors are well within 1.2. In addition, based on the ABCD matrix theory, the impact of mode matching and the thermal lens effect on the OPO output have been analyzed. (C) 2008 Optical Society of America.