Exciton–photon correlations in carbon nanotubes

We study theoretically the interactions of excitonic states with surface electromagnetic modes of a semiconducting carbon nanotube. We show that these interactions result in the exciton–plasmon coupling which may be significant in its strength due to the presence of the low-energy (∼0.5–2 eV) interband plasmon modes and large exciton excitation energies of ∼1 eV in the small-diameter single-walled nanotubes.