Using noncritically phase-matched 1-cm<sup>2</sup> -aperture KTiOAsO<sub>4</sub> (KTA) crystals in an optical parametric oscillator (OPO), we have demonstrated a sustained average signal power of 33 W at 1534.7 nm. To our knowledge, this is the highest-average-power signal ever generated by an OPO. The pump source was a 100-Hz <i>Q</i> -switched 1064-nm Nd:YAG laser. Compared with that of the similar and more-common material KTiOPO><sub>4</sub> , idler absorption in KTA is negligible, allowing high-power operation with minimal thermally induced refractive distortion in the OPO crystal.
© 1998 Optical Society of America
Mark S. Webb, Peter F. Moulton, Jeffrey J. Kasinski, Ralph L. Burnham, Gabe Loiacono, and Richard Stolzenberger, "High-average-power KTiOAsO4 optical parametric oscillator," Opt. Lett. 23, 1161-1163 (1998)