Electromagnetic waves in an infinite isotropic dielectric plate enclosed by two parallel perfect conductors

Electromagnetic (EM) plane-wave propagation is analyzed for an infinite isotropic dielectric plate and its surrounding free space enclosed by two parallel perfect conductors which are of equal distance from the faces of the dielectric plate. Exact solutions are obtained satisfying the three-dimensional Maxwell's equations, the continuity conditions at the interfaces of the dielectric plate and free space, and the electric boundary conditions at the faces of the perfect conductors. Dispersion relations are obtained for both the transverse electric (TE) and transverse magnetic (TM) waves. Dispersion curves are computed and analyzed for frequency branches with both real and imaginary wave numbers. The partition of energy, i.e. the ratio of EM energy per unit area in the dielectric plate to that in the surrounding free space are calculated as a function of frequency for both TE and TM waves. The effect of the gap between the shielding conductor and the face of the dielectric plate and the effect of the relative dielectric permittivity on the energy partition are examined systematically.