Ultrathin dual-functional metasurface with transmission and absorption characteristics

A dual-functional metasurface with simultaneous transmission and absorption characteristics is proposed and demonstrated by experiment. The ultrathin metasurface is composed of periodic metallic disks and split rings. The transmission band is surrounded by multiple absorption bands by properly designing the geometry of the structure. A maximum transmission of 63.8% is experimentally observed in the transmission band, and the measured absorption spectrum agrees well with numerical result. Furthermore, the designed metasurface is insensitive to the polarization states of the incident electromagnetic (EM) waves at normal incidence due to its structural symmetry.