AMPLITUDE NOISE AND LINEWIDTH REDUCTION OF AN AR+ LASER

Frequency modulation spectroscopy is used to frequency stabilize an Ar + laser at 515 nm with respect to a commercial passive cavity. Two tra nsducers, a slow and a fast one, are used. The fast transducer is also used to perform amplitude stabilization of a laser beam. Measured amp litude and frequency spectral noise densities are reported, A simplifi ed scheme of the circuitry used to reduce amplitude noise is shown. No ise characteristics of the realized system are adequate to perform spe ctroscopy of hyperfine-structure transitions of molecular iodine.