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arXiv · 2608.14279

A Reflective Metasurface for High-Efficiency Terahertz Cross-Polarization Conversion

Muhammad Fayyaz Kashif·Shobit Agarwal·Antonio Iodice·Daniele Riccio·Junaid Yaseen·Zahra Mazaheri·Gian Paolo Papari·Antonello Andreone
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Abstract

We demonstrate a reflective terahertz (THz) polarization conversion metasurface based on a double-ring aluminum resonator on a quartz substrate. Full-wave simulations are used to optimize the unit-cell geometry and investigate the polarization conversion mechanism through phase analysis, polarization ellipses, and surface-current distributions. The proposed metasurface exhibits a near-unity polarization conversion ratio (PCR) at resonance frequencies of 0.333 THz and 0.361 THz. Reflection-mode terahertz time-domain spectroscopy (THz-TDS) measurements show good agreement with the simulated results. The measured PCR exceeds 87% at both resonance frequencies, demonstrating efficient reflection-mode polarization conversion.

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Muhammad Fayyaz Kashif, Shobit Agarwal, Antonio Iodice, Daniele Riccio, Junaid Yaseen, Zahra Mazaheri, Gian Paolo Papari, Antonello Andreone. 2026-08-14. A Reflective Metasurface for High-Efficiency Terahertz Cross-Polarization Conversion. https://arxiv.org/abs/2608.14279

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