Sum-frequency generation of continuous-wave sodium D_2 resonance radiation

Abstract

Sum-frequency generation utilizing two cw single-mode Nd:YAG lasers and a congruent lithium niobate crystal yielded 3.4 mW of very narrow-band (10 kHz over 1 ms) tunable 589-nm cw radiation. This simple solid-state light source is well suited for high-resolution spectroscopy of the sodium D(2) line, as was demonstrated with both conventional and FM-modulated saturation spectroscopy.