Description and characterization of plasmonic Gaussian beams

In this work, we present for the first time a detailed description and experimental characterization of plasmonic Gaussian beams (PGBs), as well as the analytical expression to describe their field and intensity distributions. The propagation parameters of the PGBs, such as the divergence angle, Rayleigh range, beam width function, and the beam waist are determined experimentally in accordance to the proposed model. The radius of curvature of the wavefront and the Gouy phase shift of PGBs can also be predicted using this method.