Effect of substrate on optical bound states in the continuum in 1D photonic structures

Abstract

In this work, we analyze properties of BIC in CMOS-compatible one-dimensional photonic structure based on siliconon-insulator wafer at telecommunication wavelengths, where the absorption of silicon is negligible. We reveal that a high-index substrate could destroy both off-Γ BIC and in-plane symmetry protected at-Γ BIC turning them into resonant states due to leakage into the diffraction channels opening in the substrate.