Plasmon resonance in split-ring resonator based heterostructures

Abstract

We herein propose a plasmonic nanostructure that is composed of heterogeneous metallic split-ring resonator (SRR) trimers with built-in crosses. We studied its optical transmission properties by using finite difference time domain (FDTD) method. Results showed that, the resonant modes can be changed when the nanostructures are composed of different types of metals. For the heterogeneous metallic SRR trimers, the resonant modes were in the near-infrared region blue shift, but the modes remained the same when the air slit width was increased. All the dips red-shifted as dielectric constant of the SRRs medium was increased. The resonant modes in the visible region red shifted when the arms of metallic cross length were increased, but locations of resonance dips in the near-infrared region remained unchanged. Magnetic and electric field distributions for certain wavelengths were also investigated.