π and π + σ plasmon localization in single-walled carbon nanotube meta-materials

We have investigated the plasmon excitations and interband transitions in nematic nanotube meta-materials with different nanotube mean diameters. While the characteristic optical low-energy transitions give testimony to the differing mean diameters, the full momentum resolved π as well as π + σ plasmon response of the meta-materials is found to be entirely invariant with the nanotube diameters 1 nm < d < 2 nm. We hence demonstrate that plasmons on single-walled carbon nanotubes are fully channeled to be one dimensional in the typical range of nanotube diameters. The internal morphology of the meta-material offers a knob to uniformly tune the plasmon resonances.