Lattice resonances in high-index dielectric films containing nanoholes

Abstract

Surface lattice resonances (SLRs) refer to optical collective excitations existing in arrays of metallic or dielectric nanoparticles. In this paper, we study the optical properties of high-index dielectric films containing rectangle nanohole arrays and reveal the appearance of SLR-like resonance, lattice resonances (LRs), in the films. Two types of LRs, i.e., electric-dipole (ED) and magnetic-dipole (MD) LRs, originating from coupling of localized ED (or MD) excitation to TE (or TM) waveguide modes in the film, have been identified. Analytical formulas have also been derived, which predict well the resonance wavelength of the two types of LR modes. The LRs of the high-index dielectric nanohole array are found to be highly sensitive to structure parameters. By adjusting the structure parameters, a high-Q resonator with a Q factor up to 1600, narrow-band linear polarizer with a high extinction ratio, and high-quality polarization-independent mirror have been suggested. These results may be valuable for designing low-loss optical devices.