We present a graphene-based metasurface that can be actively tuned betweendifferent regimes of operation, such as anomalous beam steering and focusing,cloaking and illusion optics, by applying electrostatic gating withoutmodifying the geometry of the metasurface. The metasurface is designed byplacing graphene nano-ribbons (GNRs) on a dielectric cavity resonator, whereinterplay between geometric plasmon resonances in the ribbons and Fabry-Perotresonances in the cavity is used to achieve 2$\pi$ phase shift. As a proof ofthe concept, we demonstrate that wavefront of the field reflected from atriangular bump covered by the metasurface can be tuned by applying electricbias so as to resemble that of bare plane and of a spherical object. Moreover,reflective focusing and change of the reflection direction for theabove-mentioned cases are also shown.
展开▼
