Highly confined light guiding in a groove-coupled hybrid Bloch surface waveguide

A hybrid Bloch surface polarized waveguide comprising a dielectric nanowire incorporated at the top of a photonic crystal slab with a sandwiched dielectric arc groove is proposed, and the guiding properties of which are theoretically investigated at the telecommunication wavelength. The introduction of the arc groove offers additional freedom for tuning the supported hybrid mode. By properly choosing the geometrical parameters of the structure, the modified hybrid waveguide could feature significantly enhanced field confinement ability combined with long-range propagation length. The proposed waveguide is shown to be able to enable obviously improved optical guiding performance over the conventional hybrid Bloch surface waveguide due to the tight hybridization of the dielectric mode and the Bloch surface mode in the groove gap. The structure being studied is expected to open up a new route for high-performance photonic integrated devices.