1.1-W single-frequency 532-nm radiation by second-harmonic generation of a miniature Nd:YAG ring laser

A compact and efficient source of cw single-frequency radiation at 532 nm with excellent long-term stability has been realized by external frequency doubling of a diode-pumped miniature Nd:YAG ring laser. With a semimonolithic MgO:LiNbO(3) resonator an optical-to-optical conversion efficiency of 89% from 1064 to 532 nm at an output power of 1.1 W was achieved, with a wall plug efficiency of 9%. This system represents an ideal pump source for narrow-linewidth cw optical parametric oscillators with good frequency stability.