Efficient side-coupling configuration for photonic crystal nanobeam cavities with micro-ring resonators

This paper presents the design and optimization of a side-coupled photonic crystal nanobeam (1D PhC) cavity incorporating micro-ring resonators and a bus waveguide for efficient light coupling. The innovative design incorporates a parabolic taper function, ensuring gradual mode-gap modulation and robust light confinement. Through rigorous numerical simulations and optimization of key parameters-including the 1D PhC period, cavity center radius, taper delta radius, number of taper and mirror holes, waveguide width, ring radius, coupling gap distance, and material refractive index-we achieved a remarkable maximum Q factor of 2.5 x 105 at a wavelength of 1693.5 nm. This optimized configuration significantly enhances light-matter interaction, making it promising for applications demanding high-Q resonators.