Dichroic reflection in specular direction of Au-coated anisotropic hemispherical structure arrays based on monolayer of subwavelength-scale polystyrene spheres

In this work, we report on a dichroic reflection phenomenon in the specular direction. The reflective medium is an Au-coated anisotropic hemispherical structure (AuAHeS), composed of a polymer material, which is fabricated via a replication process based on a polystyrene (PS) spherical particle array monolayer. Structural anisotropy is provided artificially by stretching the silicone rubber mold used in the replication process. Depending on the anisotropy of the resulting structure, the absorbance spectra are significantly altered for incident light that is polarized either parallel or perpendicular to the stretching direction. Based on the optical characteristics of the structures observed in the present study, the generation of unique devices for optical, photonic, and bio-photonic applications is expected to be possible.