Graphene metamaterial for optical reflection modulation

We theoretically demonstrate an advanced optical modulator based on graphene-enabled metamaterial with voltage-controllable reflectance. A significant modulation depth of the reflection coefficient is achieved through a voltage biasing of the graphene's Fermi level, leading to an almost instantaneous change in the effective permittivity of the graphene. We show that even a single graphene layer integrated into the structure of a simple metamaterial absorber enables a relative change in the reflectance as high as 361% at near-infrared frequencies. The designed modulator may be used in optical communication systems and biomedical sensing apparatus.