CW 2ND-HARMONIC GENERATION WITH ELLIPTIC GAUSSIAN BEAMS

We present a study of the efficiency and optimization of cw second har monic generation by elliptical Gaussian laser beams. Elliptical focusi ng slightly improves conversion efficiency and reduces crystal damage risk when heavy walk-off is present. Single-pass measurements of the e fficiency for doubling 515-nm radiation in beta-barium berate (BBO) ag ree with theory. Thermal effects, caused by radiation absorption, limi t the doubling efficiency of single-frequency radiation in an external enhancement ring cavity.