Stable color-center laser in OH-doped NaCl operating in the 141- to 181-μm region

A powerful and stable color-center laser based on a perturbed F(2)(+) center has been demonstrated in additively colored NaCl:OH(-) crystals. The OH(-) impurity has been positively identified as the key dopant for creating the color-center laser in NaCl. The laser tunes smoothly over the 1.41- to 1.81-microm region with a maximum cw power of 1.25 W when pumped by a 9-W cw Nd:YAG laser operating at 1.06 microm. Laser operation for periods of several weeks has been monitored with no observable fading in output power. In addition, mode-locked pulses of 5-psec duration have been generated in a synchronously pumped arrangement, tunable from 1.47 to 1.73 microm with an average power of 450 mW at the peak of the tuning curve.