Reconfigurable free-form graphene camouflage metasurfaces

Becoming invisible is basically playing with the reflection spectra, where we can either rebuild the original propagating ray traces to cloak an object as if it never existed, or alternatively, conceal the reflected beams by perfectly absorbing all the incidences. In this Letter, a graphene based camouflage metasurface is proposed to carpet the randomly distributed metallic blocks on the ground. We show that the reflected traces could be reconstructed efficiently into the desired directions from any shape of graphene based metasurface simply by tuning the Fermi energy of the graphene patches. Meanwhile, the intensity of the reflections can also be disguised into the background spectra with the consideration of the inevitable reduced energy reflecting from the ground with lossy compositions or disordered scattering fields from uneven surfaces. Our approach of designing the graphene based metasurface coating is versatile for reconfigurable free-form camouflage under illumination from different incident angles and also demonstrates the possibility of creating diffuse reflections to escape detection.