Cavity-enhanced single-frequency synthesis via difference-frequency generation of mode-locked pulse trains

We show how to synthesize a cw, single-frequency optical field from the frequency-dispersed, pulsed field of a mode-locked laser. This process, which relies on difference-frequency generation in an optical cavity, is efficient and can be considered as an optical rectification. Quantitative estimates for the output power and amplitude noise properties of a realistic system are given. Possible applications to optical frequency synthesis and optical metrology are discussed. (c) 2005 Optical Society of America.