Figure 4

(Top) EM field distribution of a system composed of Ni nanowires. Embedded in an n = 1.4 dielectric medium and surrounded by an n = 1.7 shell for different thicknesses, at the energies where the LSP is excited (maximum field concentration within the nanowire). (Bottom) Same as in top but for a system composed of Ni nanowires embedded in an n = 1.7 dielectric medium and surrounded by an n = 1.4 shell. In both cases, the inner and outer dashed rings delimit the nanowire and shell sections, respectively. (Graph) Average EM field intensity within the Ni nanowires as a function of the shell thickness. The continuous and dotted lines correspond to different uniform background mediums (n = 1.7 and n = 1.4 refractive indexes, respectively), whereas circles (dots) correspond to the system described at top (bottom).