Optical properties of metal nanoparticles as probed by photoemission electron microscopy

Abstract

Interaction of light with metallic nanostructures exhibit resonances specific to eigenmodes of collective electron motion known as plasmon modes. Both these resonances and effects of electromagnetic singularities lead to local field enhancement. Photoemission electron microscopy (PEEM) was recently used to image the electrons photoemitted from these local effects. Here we report on a full PEEM spectral study of localized surface plasmons excited on nanoparticles. In particular, we show strong spectral similarities between the PEEM signal and optical extinction as a function of the incident wavelength, establishing the photoemission microscopy as a valuable tool for investigating the optical properties of metal nanoparticles.