Figure 2
From: Unveiling quasi-dark surface plasmon modes in Au nanoring cavities by cathodoluminescence
Comparison of the calculated CL and scattering spectra, and the normalized amplitude distributions. (a) Calculated CL emission spectrum (black) for a single Au nanoring with inside radius 80 nm and thickness 100 nm surrounded by vacuum, compared to the calculated scattering cross section (red) by plane wave excitation under normal incidence. (b) Calculated H z field in x-y plane for r = 80 nm nanoring at λ = 954 nm (m = 1) by a plane wave excitation. (c) and (d) show the calculated H z field in x-y plane for the same structure at λ = 1212 nm (m = 1) and 592 nm (m = 2) by 30 keV electron beam excitation, respectively. The electron beam was positioned at r = 120 nm and the cuts are taken at 10 nm above the upper surface. The black dashed circles indicate the edge of the structure.
