We report 95% conversion from the optimized Q-switched fundamental output to green output in the self-frequency doubling material Yb:YAB. Maximum average green powers of 2.27 W were obtained at 520-522 nm. The diode-to-green conversion efficiency was 26%. Operating at 10 kHz we obtained pulse widths ranging from 100 ns to 2 µs. The pulse duration was critically dependent on the strength of the nonlinear coupling and on the time that the acousto-optic Q switch was open. Numerical modeling of the system is found to predict the observed pulse-lengthening effect as well as high-average-power second-harmonic generation over a broad wavelength range.
© 2005 Optical Society of America
(140.3480) Lasers and laser optics : Lasers, diode-pumped
(140.3540) Lasers and laser optics : Lasers, Q-switched
(140.3600) Lasers and laser optics : Lasers, tunable
(190.2620) Nonlinear optics : Harmonic generation and mixing
Peter Dekker, Judith M. Dawes, and James A. Piper, "2.27-W Q-switched self-doubling Yb:YAB laser with controllable pulse length," J. Opt. Soc. Am. B 22, 378-384 (2005)