Absolute frequency stabilization of diode-laser-pumped Nd:YAG lasers to hyperfine transitions in molecular iodine

Diode-laser-pumped Nd:YAG lasers were frequency stabilized by locking their frequency-doubled output to Doppler-free absorption lines of the (127)I(2) molecule. The successive two-sample deviation of the beat frequency between two independent iodine-stabilized lasers is less than 650 Hz, or 2.3 x 10(-12) of the laser frequency, for averaging times between 24 and 80 s.