Dispersion Characteristics of Asymmetric Channel Plasmon Polariton Waveguides

A novel asymmetric channel plasmon polaritons (CPPs) is proposed and analyzed. In this paper, the dispersion characteristics of asymmetric two and three-trenched CPPs structures are studied in detail. The suggested asymmetric structures have advantages in terms of propagation length and figure of merit over the symmetric CPP waveguides. In addition, a comparative study of various CPP metals including gold and silver is also presented. It is found that the propagation length and figure of merit of the silver-based structures are better than those of gold-based structures. In addition, the effect of bending on the asymmetric CPP waveguides is investigated. The simulation results are obtained by full-vectorial finite difference method with irregular meshing capabilities and perfectly matched layer boundary conditions.