Geometric Sensitivity of Mode Hybridization in Symmetric and Asymmetric Nanoscale Dimers

Nanoparticles exhibit optical and infrared sensitivity useful in optoelectronics, spectroscopy, and sensing. Capacitative and conductive coupling induces dipolar and charge transfer plasmon modes in nanoscale dimers. Optical and infrared activity of these hybridized modes are exquisitely sensitive to geometric features of the nanoscale dimer. This study examined spectra for 7 to 8-nanometer dimers with symmetric or asymmetric radii using discrete dipole approximation. Variations in optical and infrared activity were attributable to field localization due to geometry-induced hybridization. Methods herein are useful guides to design dimers for optoelectronic, spectroscopic, and sensing applications.