Synchronization of nonsolitonic Kerr combs
Bok Young Kim's paper, "Synchronization of nonsolitonic Kerr combs," has been published by Science Advances.
Synchronization is a natural phenomenon that can occur with coupled nonlinear oscillators and is a process that allows the operating frequencies to become identical. In this article, synchronization is demonstrated between to two optical frequency combs generated using normal group velocity dispersion (GVD) coupled microresonators. Generation in the normal GVD regime allows for access to optical pulse structures with extremely high generation efficiency and flatter spectral profiles. Usually, separate combs will not be identical even if they are generated in an identically designed microresonator due to fabrication and environmental fluctuations. However, synchronization allows for the two combs to overlap in their comb lines and be coherently combined. By synchronizing two nonsolitonic normal GVD combs, the high generation efficiency of a single comb can be maintained while doubling its power per line. Because a comb can only be generated within a certain range of pump power before transitioning to other comb states (multi-pulse), this technique is useful to utilize more pump power and generate higher comb line powers that might not be in the range of a single microresonator-based comb. Applications of microresonator-based frequency combs such as data communications and spectroscopy could benefit immensely from these high comb-line powers that are otherwise inaccessible without the use of additional amplifiers.
Bok Young Kim is a PhD student in Prof. Alexander Gaeta's Quantum and Nonlinear Photonics Group. Other authors on the paper include Dr. Jae K. Jang (APAM), Dr. Yoshitomo Okawachi (APAM), Dr. Xingchen Ji (Electrical Engineering), Prof. Michal Lipson (Electrical Engineering/APAM), and Prof. Alexander Gaeta (APAM).
This work was performed, in part, at the Cornell NanoScale Facility, a member of the National Nanotechnology Infrastructure Network, which is supported by the NSF.
Funding: This work is supported by the Advanced Research Projects Agency of the U.S. Department of Energy(DE-AR0000843), the Air Force Office of Scientific Research (FA9550-15-1-0303), and the Defense Advanced Research Projects Agency of the U.S. Department of Defense (HR0011-19-2-0014).
Author contributions: B.Y.K. performed the experiment, carried out the theoretical analysis and numerical simulation, and wrote the manuscript with inputs from all the authors. B.Y.K. and J.K.J. developed the model for simulations. B.Y.K., J.K.J., Y.O., and A.L.G. contributed to the interpretation of the data. X.J. fabricated the devices under the supervision of M.L. A.L.G. supervised the overall project.