Probing Plasmonic Coupling and Symmetry Breaking in Silver Nanoprism Dimers

This study theoretically investigates the plasmonic behavior of coupled silver triangular nanoprism dimers using Electron Energy Loss Spectroscopy (EELS) simulations, comparing three distinct configurations: solid-solid (SSND), hollow-hollow (HHND), and asymmetric solid-hollow (SHND). The results show that the primary plasmon resonance in the hollow dimer is significantly redshifted compared to the solid dimer due to reduced tip polarizability. The asymmetric dimer exhibits an intermediate resonance resulting from plasmon hybridization. Most importantly, the structural asymmetry in the SHND localizes energy, confining specific modes to either the solid or hollow component. This unique property allows these asymmetric dimers to function as directional nanoantennas or selective "nanoreactors." This research provides a valuable framework for designing complex plasmonic structures with on-demand optical properties for applications like enhanced spectroscopy and photocatalysis.