Active meta-device for angular dispersion elimination of dual-polarized transmission windows

Metasurface-based strategy of tailoring electromagnetic waves has aroused huge attention in both academic and engineering communities owing to great potential in a large portfolio of applications. Commonly, however, the artificially designed metasurfaces are sensitive to the oblique incident waves which results in the angular dispersion and inevitably deteriorates the performances. Here, we propose a paradigm of an active meta-device to effectively eliminate the angular dispersion in two orthogonal polarization states of transmission waves. By loading varactor diodes into a transmissive meta-atom, the transmission responses for traverse electric (TE) and traverse magnetic (TM) waves are actively tunable by a voltage-driven manner. Accordingly, the blue shifts of transmission windows can be ingeniously compensated via tailoring the corresponding dispersion characteristics of varactor diodes. A triple-layer meta-atom loaded with varactor diodes is designed as a dual-polarization proof-of-principle, in which the varactor diodes can be applied to independently control two polarization states. The numerical simulations and experimental verification are in good agreement, indicating the proposed paradigm possesses the potential in versatile applications, including radome, wireless communications, and other dispersionless systems.