A narrow-linewidth III-V/Si/Si3N4 laser using multilayer heterogeneous integration

TL;DR

This paper presents a novel multilayer heterogeneous integration of III-V, silicon, and silicon nitride to create a high-performance, electrically pumped laser with superior stability and low phase noise, advancing integrated photonic circuits.

Contribution

It introduces a new III-V/Si/Si3N4 laser structure enabling efficient lasing in Si3N4, with improved temperature stability and phase noise, facilitating large-scale integration of Si3N4 photonics.

Findings

Demonstrated electrically pumped lasing in Si3N4 with multilayer integration

Achieved superior temperature stability and low phase noise

Provided a practical approach for integrating optical gain with low-refractive-index materials

Abstract

Silicon nitride (Si3N4), as a complementary metal-oxide-semiconductor (CMOS) material, finds wide use in modern integrated circuit (IC) technology. The past decade has witnessed tremendous development of Si3N4 in photonic areas, with innovations in nonlinear photonics, optical sensing, etc. However, the lack of an integrated laser with high performance prohibits the large-scale integration of Si3N4 waveguides into complex photonic integrated circuits (PICs). Here, we demonstrate a novel III-V/Si/Si3N4 structure to enable efficient electrically pumped lasing in a Si3N4 based laser external cavity. The laser shows superior temperature stability and low phase noise compared with lasers purely dependent on semiconductors. Beyond this, the demonstrated multilayer heterogeneous integration provides a practical path to incorporate efficient optical gain with various low-refractive-index materials. Multilayer heterogeneous integration could extend the capabilities of semiconductor lasers to improve performance and enable a new class of devices such as integrated optical clocks and optical gyroscopes.