Integrated-Circuit Enabled Adaptive Metasurface Absorber With Independent Tuning of Orthogonal Polarization Planes

A customized integrated circuit (IC) is presented that is designed specifically for implementing complex-impedance metasurface loading elements. This IC enables innovative metasurface designs that target absorption applications. Through targeted electronic and electromagnetic co-design, we propose an innovative metasurface unit cell to implement a tunable metasurface absorber. We demonstrate the proposed loading element performance range through a fabricated custom IC. Experimental measurements of the fabricated loading element circuit in a 180 nm CMOS technology are used in an electromagnetic simulator to demonstrate tunable perfect absorption at normal and oblique angles of incidence for both transverse electric (TE) and transverse magnetic (TM) polarizations. With four of the proposed loading elements, realized on a custom IC, the metasurface absorber is shown to control independently and simultaneously the absorption of both TE and TM polarizations.