Hybrid spatial-spectral integral equation for periodic guided wave problems and applications to magnetoplasmonics in graphene

A hybrid spatial-spectral integral equation (IE) is proposed for the eigenmode analysis of guided-wave periodic structures. The proposed IE uses the spatial guided-wave traveling Green function over the transverse cross section of the conducting sheet and Fourier series coefficients in the longitudinal direction. In this way, the original three-dimensional problem is reduced to a system of one-dimensional integral equations. The resulting equations are solved using the method of moments.