Work

Stimulated Brillouin scattering in a non-suspended ultra-low-loss thick-SOI platform

Year: 2025

Type: article

Abstract: Silicon photonics, with its CMOS compatibility and high integration density, has enabled a wide range of novel applications. Harnessing stimulated Brillouin scattering (SBS), an optomechanic interaction between optical and gigahertz acoustic waves, in silicon-on-insulator (SOI) platforms attracts great interest for its potential in narrow-linewidth lasers and microwave photonics. However, the poor optoacoustic overlap in silicon nanowires on conventional SOI platforms has previously restricted the observation of SBS signals to suspended silicon waveguide structures. In this work, we report, for the first time, the SBS response in a non-suspended ultra-low-loss thick-SOI waveguide platform. The backward SBS process in this 3 μm thick SOI platform is enabled by a leaky acoustic mode that coexists with the optical mode in the waveguide core, resulting in an enhanced optoacoustic overlap. We measured Brillouin gain coefficients of 2.5 and 1.9 m−1 W−1 at 37.6 GHz for the rib and strip waveguides, respectively. This work paves the way for Brillouin-based applications in non-suspended ultra-low-loss silicon photonics systems.

Source: APL Photonics

DOI: 10.1063/5.0246281

Authors: Kaixuan Ye, Akshay Keloth, Yisbel E. Marin, Matteo Cherchi, Timo Aalto, David Marpaung

Institutions: University of Twente, VTT Technical Research Centre of Finland

Language: English

Topic: Photonic and Optical Devices

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,750

Funders: Nederlandse Organisatie voor Wetenschappelijk Onderzoek, HORIZON EUROPE European Research Council