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

Abstract

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 TiO 2 nanostructures, but, only for frequencies from the range of the surface plasmon polaritons of respective materials. The TiO 2 nanostructure films for a classic cylindrical polytetrafluoroethylene cell was synthesized in our experiments too.