title: Tailoring directional scattering through magnetic and electric resonances in subwavelength silicon nanodisks.
abstract: Interference of optically induced electric and magnetic modes in high-index all-dielectric nanoparticles offers unique opportunities for tailoring directional scattering and engineering the flow of light. In this article we demonstrate theoretically and experimentally that the interference of electric and magnetic optically induced modes in individual subwavelength silicon nanodisks can lead to the suppression of resonant backscattering and to enhanced resonant forward scattering of light. To this end we spectrally tune the nanodisk's fundamental electric and magnetic resonances with respect to each other by a variation of the nanodisk aspect ratio. This ability to tune two modes of different character within the same nanoparticle provides direct control over their interference, and, in consequence, allows for engineering the particle's resonant and off-resonant scattering patterns. Most importantly, measured and numerically calculated transmittance spectra reveal that backward scattering can be suppressed and forward scattering can be enhanced at resonance for the particular case of overlapping electric and magnetic resonances. Our experimental results are in good agreement with calculations based on the discrete dipole approach as well as finite-integral frequency-domain simulations. Furthermore, we show useful applications of silicon nanodisks with tailored resonances as optical nanoantennas with strong unidirectional emission from a dipole source.
authors: Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University , Canberra ACT 0200, Australia.
authors: Isabelle
authors: I
authors: Staude
authors: Andrey E
authors: AE
authors: Miroshnichenko
authors: Manuel
authors: M
authors: Decker
authors: Nche T
authors: NT
authors: Fofang
authors: Sheng
authors: S
authors: Liu
authors: Edward
authors: E
authors: Gonzales
authors: Jason
authors: J
authors: Dominguez
authors: Ting Shan
authors: TS
authors: Luk
authors: Dragomir N
authors: DN
authors: Neshev
authors: Igal
authors: I
authors: Brener
authors: Yuri
authors: Y
authors: Kivshar