Optical response of anisotropic silver nanostructures on polarized light

Abstract

Treatment of absorbing polymer (polyethyleneterephthalate) with pulse KrF excimer laser causes formation of laser induced periodic surface structures (LIPSS). Silver nanowires were prepared on the surface of laser treated polymer using vacuum evaporation at glancing angle geometry (70°). The wires were observed with Scanning Electron Microscope equipped with Focused Ion Beam module (FIB-SEM). Relations between size and spacing of wires and morphology of polymer template were observed from those images. Optical response of prepared wires with different cross-sections and spatial parameters was investigated. The effect of polarizer on measured UV–vis absorption spectra showed anisotropy in optical properties of 1D metal nanostructures. The excitation of Localized Surface Plasmon Resonance (LSPR) was achieved only with an appropriate arrangement of the wire axis to the plane of polarization. Influence of wire width on position of absorption band was detected. Wire thickness was found to be a crucial parameter resulting in plasmon peak intensity.