Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Hybrid InP and SiN integration of an octave-spanning frequency comb



Travis Briles, Su P. Yu, Lin Chang, Chao Xiang, Joel Guo, David Kinghorn, Gregory Moille, Kartik Srinivasan, John E. Bowers, Scott Papp


Implementing optical-frequency combs with integrated photonics will enable wider use of precision timing signals. Here, we explore the generation of an octave-span, Kerr-microresonator frequency comb, using hybrid integration of an InP distributed-feedback laser and a SiN photonic-integrated circuit. We demonstrate electrically pumped and fiber-packaged prototype systems, enabled by self-injection locking. This direct integration of a laser and a microresonator circuit without previously used intervening elements, like optical modulators and isolators, necessitates understanding self-injection-locking dynamics with octave-span Kerr solitons. In particular, system architectures must adjust to the strong coupling of microresonator back-scattering and laser-microresonator frequency detuning that we uncover here. Our work illustrates critical considerations towards realizing a self-referenced frequency comb with integrated photonics.
Applied Physics Letters Photonics


Frequency comb, microresonator, photonic integration, soliton, self-injection locking


Briles, T. , Yu, S. , Chang, L. , Xiang, C. , Guo, J. , Kinghorn, D. , Moille, G. , Srinivasan, K. , Bowers, J. and Papp, S. (2021), Hybrid InP and SiN integration of an octave-spanning frequency comb, Applied Physics Letters Photonics, [online], (Accessed April 19, 2024)
Created February 2, 2021, Updated March 25, 2024