Ultra-Sharp Transmission Resonances in Periodic Arrays of Graphene Ribbons in TE Polarization

When illuminated by TM polarized waves, periodic arrays of graphene ribbons are known to exhibit plasmonic resonances due to their dual inductive-capacitive nature. It is demonstrated here that even in TE polarization, resonances can be observed in these structure. These resonances, which are of nonplasmonic origin, are explained by means of a circuit model. It is shown that, for a certain frequency range, arrays of graphene ribbons have both capacitive and inductive properties, which lead to an ultra-sharp inductor-capacitor resonance. The banwidth of this resonance can be as narrow as similar to 0.0002 nm at a wavelength of 630 nm. The resonance can also be viewed as the grating excitation of a TE mode on graphene. The resonance properties in terms of different parameters are also invedtigated.