Raman-assisted coherent, mid-infrared frequency combs in silicon microresonators

TL;DR

This paper reports the first low-noise mid-infrared frequency comb generated in silicon microresonators, highlighting the role of Raman scattering and four-wave mixing in comb formation, and analyzing the intracavity dynamics with integrated detection.

Contribution

It introduces a novel low-noise mid-IR frequency comb source in silicon microresonators and explores the underlying nonlinear interactions involved.

Findings

Observation of strong Raman scattering lines in the comb

Raman and four-wave mixing interactions assist comb transition

Intracavity comb dynamics characterized using integrated PIN diode

Abstract

We demonstrate the first low-noise mid-IR frequency comb source using a silicon microresonator. Our observation of strong Raman scattering lines in the generated comb suggests that Raman and four-wave mixing interactions play a role in assisting the transition to the low-noise state. In addition, we characterize, the intracavity comb generation dynamics using an integrated PIN diode, which takes advantage of the inherent three-photon absorption process in silicon.