Open AccessFano resonant all-dielectric core/shell nanoparticles with ultrahigh scattering directionality in the visible region
Author(s) -
Yuta Tsuchimoto,
Taka-aki Yano,
T. Hayashi,
Masahiko Hara
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.014451
Subject(s) - fano resonance , scattering , nanophotonics , optics , metamaterial , resonance (particle physics) , refractive index , light scattering , wavelength , dielectric , materials science , forward scatter , fano plane , core (optical fiber) , nanoparticle , plasmon , optoelectronics , physics , nanotechnology , atomic physics , mathematics , pure mathematics
We demonstrate Si-based single core/shell (Si/SiO 2 ) nanoparticles which exhibit the Fano resonance associated with ultrahigh scattering directionality. The SiO 2 shell plays a crucial role in achieving zero backscattering at the Fano resonance wavelength along with strongly-enhanced forward scattering. As a result, the front-to-back scattering-intensity ratio is five orders of magnitude greater than that of a Si nanoparticle. Furthermore, the Fano resonance wavelength is controlled over the entire visible region by changing the core diameter. The Fano spectra also show distinctive intensity modulations depending on the index of refraction of the surrounding medium. These unique features make Si/SiO 2 nanoparticles promising for the design of low-loss nano-antennas, metamaterials, and other nanophotonic devices.