Towards Real-time Independent Control of Reflection Magnitude and Phase in Electromagnetic Metasurfaces

A novel configuration of a metasurface unit cell is proposed to independently control its reflection phase and magnitude at the specified frequency and is demonstrated using an equivalent circuit model. The unit cell of the proposed metasurface structure consists of two resonators with integrated resistive and capacitive loads in each resonator, which are respectively responsible for dynamically controlling the reflection magnitude and phase. An equivalent circuit model of such confirmation is developed to study the reflection response of the metasurface as a function of various lumped-element controls. It is shown that an arbitrary combination reflection amplitude and phase can be achieved by appropriate combination of these lumped elements. Using commonly available tunable resistive and capacitive components, a real-time tunable metasurface is envisioned where the reflection amplitude and phase of the metasurface can be engineered with complete flexibility.