Electromagnetic chirality induced by graphene inclusions in multilayered metamaterials

We theoretically investigate the electromagnetic response of a novel class of multilayered metamaterials obtained by alternating graphene sheets and dielectric layers, the whole structure not exhibiting a plane of reflection symmetry along the stacking direction. We show that the electromagnetic response of the structure is characterized by a magneto-electric coupling described by an effective chiral parameter. Exploiting the intrinsic tunability of graphene-light coupling, we prove that one can tune both the dielectric and the chiral electromagnetic response by varying the graphene chemical potential through external voltage gating. (C) 2014 Chinese Laser Press