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arXiv · 2605.27528

A cavity-less architecture for high-power integrated frequency combs

Mrinmoy Roy·Joshua A. Palacios·Shuva Roy·Darren D. Hudson·Andrea Blanco Redondo
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Abstract

Photonic chip-based frequency combs have emerged as a transformative platform, enabling compact, scalable, and high-performance multiwavelength sources with far-reaching impact across science and technology. Most commonly, these sources leverage the cavity enhancement of the nonlinearities to produce a spectrum of equidistant frequency lines via cascaded four-wave mixing in high-quality microresonators pumped with a continuous wave tone. While the presence of the resonator inherently enables low-power threshold operation, it also brings intrinsic limitations in efficiency, tunability, and power per line. Here, we propose and demonstrate a cavity-less approach for the generation of optical frequency combs on-chip, which relies on non-degenerate cascaded four wave mixing in dispersion engineered integrated photonic waveguides. The results presented here enable previously inaccessible regimes of pump-to-comb conversion efficiency, wide-range continuous line-spacing tunability, and power per line for coherent comb states. This work opens new research opportunities in nonlinear integrated photonics and pathways toward high-capacity optical interconnects, scalable photonic AI accelerators, and other power-constrained integrated systems.

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Mrinmoy Roy, Joshua A. Palacios, Shuva Roy, Darren D. Hudson, Andrea Blanco Redondo. 2026-05-26. A cavity-less architecture for high-power integrated frequency combs. https://arxiv.org/abs/2605.27528

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