Waveguide Bragg gratings are expected to play an important role in diverse applications of photonic integrated circuits. Here, we present our latest progress in implementing Bragg filters with a customized spectral response in the silicon-on-insulator platform. Our filter comprises a silicon waveguide with an array of Bragg segments placed aside. The waveguide core is designed to have a reduced mode confinement, which enables an accurate control of the grating strength via modulation of the Bragg segment separation distance and allows for minimum feature sizes compatible with deep-UV lithography (>100 nm). Our design strategy is experimentally validated by demonstrating a filter with 20 non-uniformly spaced notches in the transmittance spectrum.
Palabras clave: Silicon photonics, Bragg gratings, spectral filters.