INTRACAVITY FREQUENCY-DOUBLING OF A DIODE-PUMPED 946-NM ND-YAG LASER WITH BULK PERIODICALLY POLED MGO-LINBO(3)

We report what we believe is the first cw quasi-phase-matched intracav ity frequency doubling of a diode-pumped 946-nm Nd:YAG laser by use of bulk periodically poled MgO-LiNbO3. A maximum second-harmonic power o f 5.9 mW was obtained at a laser diode power of 500 mW. The blue beam profile showed a TEM00 single spatial mode of low ellipticity (1:1) be cause there was no walk-off problem. Bulk periodic domain inversion wa s accomplished by a corona discharge method with a first-order modulat ion period of 4.75 mu m for a wavelength of 946 nm over a 2-mm interac tion length in Z-cut 0.4-mm-thick MgO-LiNbO3. (C) 1997 Optical Society of America.