Independently Controlled HEMT-embedded Metasurface for Terahertz Amplitude and Phase Modulation

An independently controlled programmable metasurface for terahertz (THz) wavefront modulation is proposed here. Based on ultrafast electrically controlled HEMT-embedded resonant structure arranged in a supercell manner, the reflective amplitude and phase can be dynamically manipulated with the variation of carrier concentrations within the two-dimensional electron gas (2DEG). Corroborated through the simulation and measurement, a 88% max modulation depth and a 111° max phase shift have been attained, which suggests the presented metasurface may motivate developments on smart surfaces for the next generation of high-speed wireless communications.