Theoretical designs for novel photonic crystal nanocavities with Si (111) interfaces

We designed a series of photonic crystal (PhC) nanocavities using atomically flat silicon (111) interfaces and examined the impacts of the surfaces on the optical confinement. The nanocavities were simulated using the 3D finite-difference time-domain method and assessed against existing PhCs. Despite the design restrictions, we showed that a Q value up to 115,800 and Q/V values of 103-105λ−3 are achievable without further design optimization. The results suggest that silicon (111) surfaces can be used for fabricating PhC nanocavity-based devices in a practical and economical way with high manufacturing tolerance and increased repeatability.