Interband and plasma excitations in single-walled carbon nanotubes and graphite in inelastic x-ray and electron scattering

The dynamical structure factor S (q,ω) in graphite, freestanding thin-bundled single-walled carbon nanotubes and bulk aligned nanotubes is probed by means of inelastic x-ray and electron scattering. We utilize the equivalency and complementarity of the two techniques in our combined approach. Both independent methods may be joined seamlessly. The joint extended experimental access to the plasmon dispersion exposes vividly the transition from screened plasmons at low momenta to uniform interband transitions at high momentum transfers.