Advancing on-chip Kerr optical parametric oscillation towards coherent applications covering the green gap

Published

August 21, 2024

Author(s)

Yi Sun, Jordan Stone, Xiyuan Lu, Feng Zhou, Ashish Chanana, Zhimin Shi, Marcelo Davanco, Kartik Srinivasan

Abstract

Optical parametric oscillation (OPO) in Kerr microresonators can efficiently transfer near-infrared laser light into the visible spectrum. To date, however, chromatic dispersion has mostly limited output wavelengths to >560 nm, and robust access to the whole green light spectrum has not been demonstrated. In fact, wavelengths between 532 nm and 633 nm, commonly referred to as the "green gap", are especially challenging to produce with conventional laser gain. Hence, there is motivation to extend the Kerr OPO wavelength range and develop reliable device designs. Here, we experimentally show how to robustly access the entire green gap with Kerr OPO in silicon nitride microrings pumped near 780 nm. Our microring geometries are optimized for green-gap emission; in particular, we introduce a dispersion engineering technique, based on partially undercutting the microring, which not only expands wavelength access but also proves robust to variations in resonator dimensions. Using just four devices, we generate >150 wavelengths evenly distributed throughout the green gap, as predicted by our dispersion simulations. Moreover, we establish the usefulness of Kerr OPO to coherent applications by demonstrating continuous frequency tuning (>50 GHz) and narrow optical linewidths (<1 MHz). Our work represents an important step in the quest to bring nonlinear nanophotonics and its advantages to the visible spectrum.

Citation

Light: Science & Applications

Volume

13

Pub Type

Journals

Download Paper

https://doi.org/10.1038/s41377-024-01534-x

Local Download

Citation

Sun, Y. , Stone, J. , Lu, X. , Zhou, F. , Chanana, A. , Shi, Z. , Davanco, M. and Srinivasan, K. (2024), Advancing on-chip Kerr optical parametric oscillation towards coherent applications covering the green gap, Light: Science & Applications, [online], https://doi.org/10.1038/s41377-024-01534-x, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956811 (Accessed October 13, 2025)