Model of finite-momentum excitons driven by surface plasmons in photoexcited carbon nanotubes covered by gold metal films.

Optical spectra of finite-momentum excitons in carbon nanotubes with gold nanostructures are theoretically studied. A Green function method is developed for self-consistently solving Maxwell equations including the quantum-mechanical nonlocal response of the nanotubes and the local response of the nanostructures. Excitons with finite momenta in the axis direction in the nanotubes are effectively excited by localized electric fields due to surface plasmons in the gold nanostructures and counteract the surface plasmons through depolarization fields, showing the crucial self-consistency of these effects.