numerical study of a nanoscale waveguide with brillouin scattering

Stimulated brillouin scattering (sbs) arises from the interaction between light and sound waves. in partially suspended waveguides, reduced substrate contact enhances optical and acoustic confinement, improving sbs efficiency. this study uses two-dimensional finite element simulations to analyze sbs in a silicon waveguide anchored by a silica pillar. both forward and backward sbs are explored across a broad frequency range. optimizing the pillar width significantly increases sbs gain, mainly through the photoelastic effect, with minor moving boundary contributions. the results emphasize the importance of structural design in enhancing sbs for high-performance integrated photonic applications.