We study the factors that ultimately limit the performance of an external enhancement resonator for optical second-harmonic generation (SHG). To describe the resonant SHG process we introduce a theoretical model that accounts for the intensity-dependent cavity loss that is due to harmonic generation and that also includes a realistic assumption about the shape and the frequency width of the laser mode. With the help of this model we optimized the performance of a doubling cavity based on a lithium triborate (LBO) crystal. This cavity was used for frequency doubling the output of a single-frequency titanium-doped sapphire laser at 850 nm. We were able to push the total second-harmonic conversion efficiency to 53% (a 1.54-W pump resulted in 820 mW of second-harmonic light), which to our knowledge is the best result ever reported for a LBO-based doubling cavity.
© 2002 Optical Society of America
E. Jurdik, J. Hohlfeld, A. F. van Etteger, A. J. Toonen, W. L. Meerts, H. van Kempen, and Th. Rasing, "Performance optimization of an external enhancement resonator for optical second-harmonic generation," J. Opt. Soc. Am. B 19, 1660-1667 (2002)