Coherent Combining for High‐Power Kerr Combs

Abstract

Kerr frequency combs enable the miniaturization of comb sources for applications such as data communications and spectroscopy. However, due to the high field confinement and effective nonlinearity, Kerr combs typically operate with low output comb powers. While nonsolitonic Kerr combs operating in the normal group velocity dispersion (GVD) regime can access high pump‐to‐comb conversion efficiencies and relatively flat spectral profiles, many frequency comb applications require even higher comb‐line powers that are otherwise fundamentally unattainable without the use of optical amplifiers. A high efficient coherent beam combining of Kerr combs is demonstrated via on‐chip synchronization to greatly enhanced comb‐line powers. Two normal GVD Kerr combs are coherently combined for a 2.9 dB increase in comb power compared to a single comb while maintaining a high total pump‐to‐comb conversion efficiency of 26%. Lastly, it is shown that via spectral engineering of two normal GVD combs, it should be possible to significantly increase the spectral flatness of a combined comb. This platform enables fully integrated systems with powers that can readily exceed that of an individual comb system by more than an order of magnitude.

Synchronization, Desynchronization, and Intermediate Regime of Breathing Solitons and Soliton Molecules in a Laser Cavity

“…Apart from being of significant interest in fundamental science, synchronization phenomena also find a wide range of practical applications. For instance, in the field of optics, the synchronization of multiple microresonators can break the power limitation of a single microresonator [3][4][5]. Breathing solitons, manifesting themselves as localized temporal or spatial structures that exhibit periodic oscillatory behavior, are fundamental modes of many nonlinear physical systems and relate to a wide range of important nonlinear dynamics.…”