Simulated localized surface plasmon spectra of single gold and silver nanobars

Gold and silver nanoparticles can exhibit localized surface plasmon resonance phenomena resulting from the interaction with light, and it is always characterized by the extinction spectrum. In this paper, the extinction spectra for single gold and silver nanobars are investigated by using discrete dipole approximation method. We present a systematic study of the effects of the orientation, the length, and the refractive index of ambient medium on the extinction spectrum and resonance wavelength of single nanobars. The results show that the nanobar can excite both the longitudinal mode and transverse mode in visible and near-infrared regions at specific conditions.