Numerical modeling, design, and time-frequncy metrology applications of low-noise optical frequency combs

Abstract

Optical frequency combs are very versatile tools, which revolutionized many ar eas, and enabled novel applications, especially in time-frequency metrology. In this thesis, I tried to convey a complete picture of the road that goes from conception through design to applications of optical frequency combs. To this end, implementation details of a free, publicly- available numerical pulse propagation simulation software, which can be used for, but not limited to, simulating and designing complete fem tosecond laser and amplifier systems, supercontinuum generation, and Raman lasers, is presented. An algorithmic design methodology, which was used for designing all of the femtosecond lasers and fiber amplifiers presented in this thesis, is introduced, which might pave the way to discovery of new laser pulse evolution regimes. Sev eral optical frequency combs were developed and utilized in time- frequency metrology applications. A fully-stabilized, robust, and transportable low-noise Yb-fiber optical frequency comb was developed and used for absolute frequency measurements of stabi lized lasers. High-harmonic mode-locking and repetition rate multiplication methods were used to generate ultra-low phase noise RF-MW signals with frequencies ranging from 78.125 MHz to 10 GHz by utilizing optical frequency combs. A femtosecond fiber laser that can be automatically mode-locked was also developed during these studies. Finally, an atomic frequency standard based on a passively mode-locked femtosecond laser was developed, for the first time to the best of my knowledge. Resulting 87Rb atomic frequency standard performed at a similar level to the commercial Rb atomic frequency standards, with much better phase noise at high frequency offsets.