DIMENSIONALITY CROSSOVERS OF THE SIGMA-PLASMON IN COAXIAL CARBON NANOTUBES

Dimensionality crossovers of plasmons in carbon nanotubes, modeled as curved layered electron-gas superstructures, are investigated. For sma ll wave vectors, the sigma plasmons exhibit a transition from a one- t o a three-dimensional character as the number of graphitic shells incr eases, in correspondence with recent experiments. For large wave vecto rs, plasmons of two-dimensional character are predicted.