Nonlocal effects in the plasmons of nanowires and nanocavities excited by fast electron beams

Abstract

The solutions of surface modes in cylindrical metallic wires and cavities are obtained within a nonlocal dielectric formalism. We compare the results with those obtained from standard local approaches. The specular reflection model is applied to describe the nonlocal potentials in the vicinity of the wires and cavities. The external probe exciting the surface plasmons are fast electron beams traveling parallel to the wires and cavities, as those commonly used in electron microscopy and cathodoluminescence. Energy-loss spectra due to surfaceplasmon excitation are calculated with use of the nonlocal formalism both for electron trajectories near a metallic nanowire and a metallic nanocavity. When nonlocal effects are considered, the intensity of the plasmon excitation is reduced, and a blueshift of the energy is observed. This effect is more pronounced for very thin wires and cavities where the cylindrical interfaces are strongly interacting. The blueshifts reported here are important for the accurate design of the plasmon response in one-dimensional metallic nanostructures.

A classical treatment of optical tunneling in plasmonic gaps: extending the quantum corrected model to practical situations

“…2,[64][65][66][67][68][69][70][71][72][73] The nonlocal hydrodynamical (NLHD) description has attracted considerable interest because of its numerical efficiency for arbitrarily-shaped objects 47,[74][75][76][77][78][79][80][81][82][83][84] and the possibility to obtain semi-analytical Example of the implementation of QCM in metallic gaps. In (a), a spatially inhomogeneous effective medium whose properties depend continuously on the separation distance is introduced in the gap between two metallic spheres.…”

High-Energy Surface and Volume Plasmons in Nanopatterned Sub-10 nm Aluminum Nanostructures

“…The nonlocal hydrodynamic model used to explain the increase in VP energy with decreasing nanodisk diameter, as shown in figure 3a, may also be used to predict an increase in VP and SP energy near the boundary. 58 Figure 4g shows that the VP energy and 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 Figure 4h shows that the Al SP intensity peaks at the Al-AlO y interface as might be expected.…”

On quantum approach to modeling of plasmon photovoltaic effect

“…Efforts to extend the original formulation of light scattering by a sphere by Gustav Mie [19] which excludes electro-optical bulk and surface effects of the conduction band electrons are made since the 1980s [60][61][62][63][64]. Advanced material models can be derived from perturbative theories [23,51], by separating the free electron dynamics from the core electron polarization via the hydrodynamic equation for an electron plasma [22][23][24][25][26][65][66][67][68][69][70][71][72][73] and from microscopic theories [30,36,74]. It was shown within the hydrodynamic framework that the electron spill-out can be adequately incorporated [75].…”

“…In recent years, a great effort to theoretically [22][23][24][25][26][65][66][67][68][69][70][71][72][73] describe and subsequently to experimentally [55][56][57]59] verify the effect of spatial dispersion in metals was made. In the hydrodynamic approach, coupling the electromagnetic wave equation…”