Plasmon-polariton oscillations in three-dimensional disordered nanotubes excited by a moving charge

We systematically investigated the plasmon-polariton oscillations generated by a fast radiating charge (Cherenkov radiation) in a three-dimensional (3D) strongly disordered nanostructure. We studied the dynamic properties of an optical field in a random composition of empty single-wall nanotubes by using a 3D numerical finite-difference time domain technique. In our approach, only parameters of nanotube structures are fixed. The dynamic spectrum of internal field excitations was left to be defined as a result of numerical simulation. The patterns of total field (charge+carbon nanotubes) are determined by the interference of a moving charge field and the spectrum of surface plasmon-polaritons in disordered nanotubes. We found that the field energy losses, as a function of the charge velocity, has a clearly pronounced maximum when the characteristic frequency scale (defined by a charge velocity) is close to the frequency of the surface plasmon-polariton resonances generated in coupled nanotubes, even at a significant level of disorder. Our studies show that the shape of the resonance peak, depending on the charge velocity, is similar for carbon and nanostructures, but, only for frequencies from the range of the surface plasmon polaritons of respective materials. The nanostructure films for a classic cylindrical polytetrafluoroethylene cell was synthesized in our experiments too.