Surface plasmon-polariton waves in a silver nanofilm at optical frequencies

Surface plasmon-polariton waves guided by a silver nanofilm are considered. Special attention is paid to the proper complex wave that occurs in a two-digit section of the dispersion characteristic of an antisymmetric wave. The results of calculations of the longitudinal wave numbers of waves are presented, taking into account the frequency dependence of the complex dielectric constant of silver at optical frequencies below the frequency of plasmon resonance.