Fully integrated ultra-low power Kerr comb generation

TL;DR

This paper demonstrates the first fully integrated, ultra-low power Kerr frequency comb generator using silicon nitride waveguides, enabling portable and robust optical frequency sources with broad spectral coverage.

Contribution

It introduces a novel dual-cavity integrated design for Kerr comb generation, achieving low-noise, broadband combs with minimal power consumption.

Findings

Generated over 100 nm spectral span

Operates with only 98 mW electrical power

First fully integrated Kerr comb source

Abstract

Optical frequency combs are broadband sources that offer mutually-coherent, equidistant spectral lines with unprecedented precision in frequency and timing for an array of applications. Kerr frequency combs in microresonators require a single-frequency pump laser and have offered the promise of highly compact, scalable, and power efficient devices. Here, we realize this promise by demonstrating the first fully integrated Kerr frequency comb source through use of extremely low-loss silicon nitride waveguides that form both the microresonator and an integrated laser cavity. Our device generates low-noise soliton-modelocked combs spanning over 100 nm using only 98 mW of electrical pump power. Our design is based on a novel dual-cavity configuration that demonstrates the flexibility afforded by full integration. The realization of a fully integrated Kerr comb source with ultra-low power consumption brings the possibility of highly portable and robust frequency and timing references, sensors, and signal sources. It also enables new tools to investigate the dynamics of comb and soliton generation through close chip-based integration of microresonators and lasers.