Polarization-frequency synergetic multiplexing terahertz metasurface

Multiplexing technology, especially electromagnetic (EM) wave multiplexing is recognized as a highly effective solution for addressing the escalating demands in high-capacity information processing and communication. Nevertheless, it is yet extremely challenging for multiplexed meta-devices, as most of them could only modulate a single degree of freedom (DoF) of EM waves. In this work, a polarization-frequency synergetic multiplexing terahertz (THz) metasurface is proposed, which can realize independent controls and polarization conversion of orthogonal linearly polarized waves in two frequency bands. The transmission efficiency reaches more than 0.8 and 0.6 at 0.7 THz and 1.1 THz, respectively. The experimental measurements are highly consistent with the simulations. Moreover, a beam deflector and orbital angular momentum (OAM) metasurface that can independently achieve simultaneous polarization and frequency multiplexing in two frequency bands are designed and simulated, and the beam deflector was measured. The results show that the polarization state of the incident wave determines the polarization state of the transmitted beams in each frequency band, respectively. The proposed metasurface is benefit for the development of multiplexing and provides an avenue for high-speed and high-capacity communication in THz band.