Nonlinearities in Silicon-based Waveguides

Abstract

Silicon photonics has emerged as a promising platform for optical communication devices and optical signal processing applications. Itscompatibility with CMOS (Complimentary Metal Oxide Semiconductor)fabrication process allows the implementation of micro-structured siliconwaveguides, making it potentially cost-efficient for future optical integratedsystems. One challenge associated with Silicon Photonics is the lack of a laser source on silicon due to its indirect bandgap. However, silicon presents a 3rd ordernonlinear susceptibility, Chi(3), two orders of magnitude higher than that in silica.This high Chi(3) value can be exploited for the design of compact optical devices, such as parametric amplifier or wavelength converters and supercontinuum sources. In this project, our goal is to design, fabricate and test silicon-based, efficient and broadband devices for Optical Parametric Amplification and Wavelength Conversion. We intend to develop a detailed model for nonlinear propagation taking into account loss mechanisms such as two-photon absorption (and induced free-carrier absorption) and plasma effects. We also intend to explore structures that enhance phase-matching condition while being robust to manufacturing variability. Fabrication of these devices will be done at Unicamp as well asexternally. We will setup all characterization methods in our lab.