Resonant enhancement of sub-THz Faraday rotation in an antiferromagnetic-semiconductor metasurface

We numerically demonstrate a compact hybrid metasurface enabling low-voltage and dual-field control of enhanced Faraday rotation in the sub-terahertz regime. The structure combines a thin-film antiferromagnet (MnF₂), exhibiting resonance near 268 GHz, with TiO₂-based memristive resonators whose plasma frequency is electrically tunable. Resonant quasi-crossing between antiferromagnetic and electronic modes results in more than sixfold enhancement of the polarization rotation compared to a bare antiferromagnetic layer. Continuous tuning of the rotation angle is achieved via simultaneous application of static magnetic and DC electric fields. Voltage-driven modulation below 1 V provides efficient electrical control of the magneto-optical response without requiring strong magnetic bias variation. The proposed platform offers a compact and energy-efficient route toward reconfigurable polarization control in sub-THz photonics, with potential applications in tunable isolators, modulators, and hybrid quantum transduction systems.