Plasmon Coupling in Gold Nanotube Assemblies: Insight from a Time-Dependent Density Functional Theory (TDDFT) Calculation

The plasmonic properties of gold nanotube assemblies are investigated using time-dependent density functional theory (TDDFT). The plasmon resonance peak of gold nanotube assemblies is strongly dependent on the polarization direction and gap distance. The optical absorption exhibits that the resonances correspond to different modes. These modes can be regarded as dipole interaction from their charge distribution. The interaction between nanotubes is opposite for different polarization direction, which causes distinct anisotropy effects in the spectral behavior. These results offer us alternative ways to tune the plasmon resonance in this structure.