Figure 2.

(a) scheme of the TE-wave propagation for an array of closely packed nanocylinders; (b) electric field mapping of surface plasmon resonances in an array of Ag cylinders with the following parameters: $\omega =3.53\mathrm{eV}$, cylinder radius $a=5$ nm, interparticle distance $\delta =1$nm; (c) comparison of analytical (purple line) and numerical (blue and red dashed lines) enhancements $|E_m/E_0{|}^2$ of the electromagnetic (EM) field in the middle of dimer. The ratio $\delta /D$ is equal to 0.1, the nanorod diameter for COMSOL simulations is $D=2a=10$nm or $1$nm, and $E_0$ is amplitude of incident light, reprinted by permission from Springer Nature: Springer Nature, Applied Physics A: Materials Science and Processing [11], Copyright 2012.