Surface lattice resonance based on periodic arrays of Si nanopillar dimers

Abstract

The periodic array of Si nanopillar dimers is proposed to form surface lattice resonance (SLR) with strong local fields and narrow line-width. In the array, Si nanopillar dimers sit on quartz substrates. The simulated results show that the line-width of SLR can be as small as 4.8 nm. While SLR can't be generated by the periodic Si nanopillar array. The advantage of introducing Si nanopillar dimers is that the near field coupling between Si nanopillar dimers enhances the Mie polarization of Si nanopillar dimers. It is conducive to generating SLR, which is originated from the coupling between the Mie polarization of individual Si nanopillar dimers and diffracted waves. The gap between dimers, Si nanopillar dimers' diameter and height, the arrays' period and the refractive index of the medium environment have important influences on SLR. This work offers a possible way for SLR applications.