General properties of the surface charge pattern of one-dimensional metallic gratings
Abstract
Under light illumination, metallic gratings present unexpected and fascinating phenomena, which are due to the complex charge patterns generated on the grating surfaces. The moving electrons are due to the launching of surface plasmon polaritons (SPPs), but only in part. We derive analytical expressions quantifying the plasmonic character of the surface charge patterns, i.e. the contribution of SPPs to its formation. The expressions have a general significance, in the sense that they may be applied to a variety of geometries and spectral ranges, irrespective of whether the grating absorbs, transmits, reflects, or how strongly it resonates.²