Efficient operation of a diode-bar-pumped Nd : YAG laser on the low-gain 1123-nm line

Efficient operation of a Nd:YAG laser on the low-gain 1123-nm transition by end pumping with the reshaped output from a 7-W diode bar is reported. Usi ng a simple standing-wave laser configuration and pumping with 5.6 W of inc ident power yielded a laser output power of 1.7 W in a near-diffraction-lim ited TEM00 mode with a beam quality factor of M-2 less than or similar to 1 .1. A unidirectional single-frequency ring laser was also constructed, yiel ding 180 mW of single-frequency output. The prospects for further increase in power by optimization of the resonator design are discussed. (C) 1999 Op tical Society of America OCIS codes: 140.3460, 140.3480, 140.3530, 140.3560 .