High-Q Fano resonance in polymer metasurface for refractive index gas sensing
Abstract
We propose a polymer metasurface designed on a silicon dioxide substrate, comprised of a periodic array of polymer cylinders with opened ring cavities. Under normal incidence and linearly polarized illumination, the structure supports nine sharp Fano resonances, achieving a maximum quality (Q) factor of 1 × 10 5 . Multipole decomposition and electromagnetic field analysis attribute these resonances primarily to toroidal dipole and magnetic quadrupole modes. As a refractive index gas sensor, the metasurface shows an exceptional sensitivity of 678.57 nm/RIU, an outstanding figure of merit (FOM) of 28274 RIU −1 , and a low limit of detection (LOD) of 1.47 × 10 −6 RIU. These performance metrics highlight its significant potential for multichannel RI gas sensing and environmental monitoring.
Fields of Study & Subjects
Plasmonic and Surface Plasmon Research
Advanced Fiber Optic Sensors
Metamaterials and Metasurfaces Applications
Publication details
- Journal / source
- Optics Letters
- Publisher
- Optica Publishing Group
- Volume
- 51
- Issue
- 5
- Pages
- 1343–1343
- Publication date
- 9 February 2026
- Language
- EN