Reconfigurable coherent perfect absorption of different polarized electromagnetic fields through vanadium-dioxide based asymmetry transmissive meta-surfaces sandwiched with graphene meta-gratings

Abstract

We demonstrate coherent perfect absorption (CPA) of different linearly polarized electromagnetic fields using an asymmetry transmissive meta-surface consisting of two outermost VO2-metal layers and symmetrical graphene meta-gratings, as well as an intermediate C-slit metallic layer. Such a five-layered cascaded VO2-metal-graphene meta-surface can perfectly trap either the x- or the y-polarized signal fields when interacting with the x-polarized control wave by imposing specific Fermi level over the graphene together with conducting- or insulating-state VO2 at 3 THz. On the other hand, y-polarized control wave can also interfere with either x- or y-polarized signal fields when the CPA of the electromagnetic wave operates at 3.65 THz. Our design, using asymmetry transmissive meta-surfaces for more advanced coherent control of different linearly polarized electromagnetic fields with the assistance of tunable materials, should pave the way for building up multipolar and multifunctional absorbers.