Analytical study for hybrid guided modes in a 7-layer plasmonic waveguide

We presented a comprehensive theoretical analysis of hybrid guided modes in a 7-layer symmetrical plasmonic waveguide, which consists of a thin metal film sandwiched symmetrically by three low/high/low-index dielectric layers. The dispersion equation for the hybrid guided mode is derived which allows us to numerically calculate the mode index and the propagation length. We have thoroughly characterized the hybrid guided modes based on our derived analytical expressions.