Semi-Classical Models of Quantum Nanoplasmonics Based on the Discrete Source Method (Review)

Works concerning the quantum effect of nonlocal screening on field characteristics in the problem of scattering a plane wave by nanoscale structures, including ones located near a transparent substrate, are reviewed. Efficient computer models for analyzing such structures are constructed by applying the discrete source method. The nonlocality effect is studied using the generalized nonlocal optical response model. The field characteristics of nonspherical layered nanoparticles deposited in an active medium or on the surface of a transparent substrate are considered. It is shown that nonlocality has a large effect on the optical characteristics in the far- and near-field regions. It is established that the nonlocality effect leads to a decrease in the intensity of surface plasmon resonance by up to 2.5 times under a small shift toward short wavelengths. In the presence of a substrate, the excitation of particles by a propagating or an evanescent wave is considered. It is shown that the largest effect is exhibited for nonspherical layered particles located in the evanescent wave region.