Abstract

Tight confinement of light in photonic cavities helps realize high optical intensity with strong field gradients. We designed a nanoscale resonator device based on a one-dimensional photonic crystal slot cavity. Our design allows for highly localized optical modes with theoretically predicted quality factors (Q factors) in excess of 10 6 . The design was implemented experimentally both in a high-contrast refractive index system (silicon), as well as in medium refractive-index-contrast devices made from aluminum nitride. We achieved an extinction ratio of 21 dB in critically coupled resonators using an on-chip readout platform with loaded Q as high as 33,000. Our approach holds promise for ultrasmall optomechanical resonators for high-frequency operation and sensing applications.