Quantum transport and current distribution at radio frequency in multiwall carbon nanotubes

Multiwall carbon nanotubes represent a low-dimensional material that could serve as building blocks for future carbon-based nanoelectronics. The understanding of the electromagnetic performances at radio frequency of these materials for use in nanointerconnects is strictly related to the analysis of their transport properties as function of the working conditions. In this paper, we present an explicit expression of the conducting channels as function of diameter, temperature, doping, and supply voltage for both metallic and semiconducting carbon nanotubes. The proposed formula is based on the Dirac cone approximation of the conducting band energy of graphene nearby the Fermi points, combined with the Landauer-Buttiker formalism. Simplified expressions are also obtained in case of large diameter nanotubes. We show that the conductance, kinetic inductance, and quantum capacitance of each carbon shell are strongly affected by those parameters, and, consequently, that the current distribution among the shells of a multiwall carbon nanotube at radio frequency could be optimized with the proper definition of the nanotube configuration versus the working conditions.