Multifunctional Reflective Metasurface to Independently and Simultaneously Control Amplitude and Phase with Frequency Tunability

Abstract

The capability to dynamically modulate electromagnetic wavefronts can revolutionize and be crucial for future wireless technology. Electromagnetic waves can be fundamentally described in terms of amplitude, phase, polarization, and angular frequency. However, reported reconfigurable metasurfaces can only control one or two fundamental parameters and require different tuning/switching elements or materials that remain challenging to control those continuously. In this work, an approach is presented for designing electrically tunable reflective metasurfaces that enable independent and simultaneous control of amplitude and phase, while also providing frequency tuning capability. This is achieved by arranging two varactor diodes on the top layer and a lumped resistor on the bottom layer. The proposed metasurface is fabricated and several electromagnetic functionalities experimentally demonstrated as proof-of-concept applications, including reflector, radar absorbing, dual and single-beam steering, and amplitude control. The proposed metasurface will open avenues for realizing advanced multifunctional devices to fully control electromagnetic parameters, offering numerous applications in future communication technologies, radar systems, and information processing.