Electromagnetic energy within coated cylinders at oblique incidence and applications to graphene coatings

We address electromagnetic (EM) wave scattering by an infinite coated cylinder at an arbitrary incidence angle. The time-averaged EM energy stored inside the core-shell cylinder is analytically calculated for TM- and TE-polarized incident plane waves. An analytical expression relating the internal energy to the absorption cross section is derived. As an application, the EM energy inside dielectric cylinders coated with isotropic graphene layers epitaxially grown on silicon carbide (SiC) is studied. We find that off-resonance field enhancement occurs in graphene SiC microshells for TM-polarized terahertz waves, a phenomenon that can be explained in terms of Fano resonances.