Closed-form analysis of dispersive properties for multilayered waveguiding structures

Various dispersive properties of arbitrary multilayered waveguiding lossless structures are stated, generalizing what is already known for basic single slabs. These features enable us to derive simple but rigorous closed-form expressions for the calculation of the number of propagating surface waves; these expressions are also useful for an effective location of the relevant cutoff frequencies. The proposed analysis for the fundamental modal characterization of multilayered structures in terms of their physical and geometrical parameters allows one to avoid an often complicated numerical search for the solution of typical transcendental equations.