Leontovich-Levin equation taking into account finite conductivity of a conductor

A generalization of the Leontovich-Levin equation for current in an ideally conducting linear vibrator to the case of a finite-conductivity conductor is considered. This generalization is valid for strong and weak skin effects, as well as for inhomogeneous conductors with an axisymmetric conductivity distribution (in particular, for carbon nanotubes, CNTs). The internal structure of the conductor is fully described by the internal impedance per unit length. A recurrent scheme is proposed for calculating such an impedance for layer-inhomogeneous conductors. A particular case of the impedance for metallic achiral CNTs is considered, and substantial differences between this case and the macroscopic model of a conductor with full skin effect are indicated.