Device performance of standard strip, slot and hybrid plasmonic μ-ring resonator: a comparative study

In this paper, we presented three mu-ring resonator structures based on the standard strip, slot and hybrid plasmonic waveguides based on the SOI platform. A standard strip waveguide is formed by depositing a silicon core on a silica substrate. Whereas the slot waveguide is tailored by keeping a narrow air gap between two silicon strip waveguides. Finally, the hybrid plasmonic waveguide is composed of Metal-Air-Silicon structure, where the E-field is significantly enhanced in the narrow air gap. The ring radius is kept at 1.5 mu m for the three designs. The transmission spectrum and E-field distribution of these structures are simulated using the finite element method (FEM). Silicon strip waveguide-based ring resonators are easy to fabricate but their sensitivity is quite low as compared to the other two designs. mu-ring resonator based on hybrid plasmonic waveguide shows the best sensitivity of 333.3 nm/RIU. While, slot waveguide based mu-ring resonator showed the best performance in the quality factor, the figure of merits and limit of detection. We believe that this comparative study will facilitate the researchers to choose the suitable waveguide design for ring resonators depending on their preferred application and fabrication technology available.

Automated summary

This paper presents three mu-ring resonator structures based on silicon strip, slot, and hybrid plasmonic waveguides. Among the three designs, the mu-ring resonator based on hybrid plasmonic waveguide shows the highest sensitivity, while the slot waveguide-based mu-ring resonator exhibits the best performance in quality factor, figure of merits, and limit of detection.