Streamlined, Ultralow Noise, Portable Frequency Comb Device

Greatly reduces the overall system size and power consumption Reduces phase noise Increases the overall cavity Q Enables measurement of extremely low phase noise

High-precision radar Next generation optical clocks GPS Fiber optic communications Communication broadcasting and receiving Signal intelligence Signal processing Clock recovery

This invention includes an ultralow noise, portable frequency comb device based on a fiber cavity mode-locked laser using semiconductor optical amplifiers as the gain elements, combined with an environmentally stable macroscopic Fabry-Pérot etalon as a secondary optical reference. This device uses regenerative mode-locking, thus the laser is not slaved to an electronic reference. The ultrahigh finesse etalon, located inside the laser, serves as the stable optical reference to which all error signals and stabilization are referenced. In comparison to current technologies that create optical linewidths at the sub Hz level, this device creates ultra-narrow, optical comb lines with Hz level linewidths. This design decouples and independently stabilizes the carrier envelope offset frequency and repetition rate fluctuations by using a linear optical frequency division that reduces RF noise by a factor of 10log(N2), where N is the optical bandwidth of the mode-locked laser divided by the pulse repetition rate.

USA