Symmetric multilayer slab waveguide structure with a negative index material: TM case

The present paper deals with the theoretical modeling of symmetrical multilayer planar waveguide structure. One of the layers is considered as a negative refractive index material. We take the appropriate field distributions for p-polarization and impose the boundary conditions to derive the mode equation and other necessary formulae for the proposed structure. The effect of the negative-index layer on the modal refractive index, power flow, and penetration depth of the waveguide is studied. Also, we compare our computed results with those obtained for a similar conventional four-layer structure. It is observed that the presence of the negative-index material reduces the power flowing in the guiding layer and enhances the power flowing in the surroundings.