Progress in making stable laser sources which can be used as local oscillators for an optical atomic frequency standard is reported. For short-term stability, the laser frequency was stabilized to the resonance frequency of a high-finesse Fabry-Perot cavity. Linewidths of 50 mHz (FWHM) for He-Ne lasers and 0.49 Hz (FWHM) for a commercial dye laser system were obtained. By locking the optical phase of a commercial dye laser system to a reference laser, more than 97% of the power could be put into the carrier, which means 97% of the dye laser power is within the linewidth of the reference laser. With both passive and active vibration isolation of the optical table on which the reference cavities are mounted, 1- mu g seismic vibration and 1- mu rad tilt environment, corresponding to 20-Hz laser frequency excursion and 10-Hz frequency shift, respectively, were obtained. The long term drift was also studied.
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