Abstract
The design of an all-dielectric nanoantenna based on nonradiating “anapole” modes is studied for biosensing applications in an aqueous environment, using FDTD electromagnetic simulation. The strictly confined electromagnetic field within a circular or rectangular opening at the center of a cylindrical silicon disk produces a single point electromagnetic hotspot with up to 6.5x enhancement of |E|, for the 630-650 nm wavelength range, and we can increase the value up to 25x by coupling additional electromagnetic energy from an underlying PEC-backed substrate. We characterize the effects of the substrate design and slot dimensions on the field enhancement magnitude, for devices operating in a water medium.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 7196-7212 |
| Number of pages | 17 |
| Journal | Optics Express |
| Volume | 27 |
| Issue number | 5 |
| DOIs | |
| State | Published - 2019 |
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics