Absolute frequency stabilisation of a 637 nm laserdiode using Doppler-free I 2 spectra

Abstract
Doppler-free saturated features for two 127I2 B-X transitions have been observed in third derivative form, using an extended-cavity 637 nm laser diode. Frequency stabilisation of a visible laser diode to Doppler-free iodine features is reported for the first time. Absolute frequency measurements of the stabilised laser and a preliminary estimate of its stability are presented.