Electromagnetic Field Propagation in the One-Dimensional Silver Nanoparticle Dimer Chains: Hotspots and Energy Transport

Abstract

Strong local electromagnetic (EM) fields and efficient EM energy transport in metallic nanostructures are two important issues in their applications in quantum computations/communications. We investigate the propagation characteristics of the hotspots in one-dimensional silver nanoparticle dimer chains, which combine the functions of the gap field enhancement and the waveguide. The near field and the far field induced interplay among the local field enhancement, the radiative interaction, and the dissipation affects significantly the EM field transport efficiency. Moreover, the correlation between local structure and global structure leads to the structure-dependent excitation. With the help of the combined effects of the structure-dependent excitation, the field confinement and the propagation, the efficient EM field excitation, and long-range propagation can be obtained by tuning the structure of our systems. With suitable geometric parameters (dimer orientations, dimer gap sizes) of our system, the electric field intensity at the position 5000 nm away from the starting point (exciting point) is about 50 times of the corresponding field intensity in a silver nanoparticle chain.