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arXiv · 2012.03252

Substrate-free THz focal plane metamaterial array with high absorption ratio

Zhigang Li·Yi Ou·Xubiao Peng·Jianyu Fu·Wen Ou·Wenjing Jiang·Qing Zhao
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Abstract

Microelectromechanical system (MEMS) focal plane array (FPA) with optical readout offers exciting opportunities for real-time terahertz (THz) imaging. However, conventional FPA suffers from a low THz absorption ratio, which further decreases the performance of THz imaging. Here, we present a simple and scalable approach for the realization of THz focal plane metamaterial array with a relatively high absorption ratio. The key idea is to combine the advantages of substrate-free structures with metamaterial. A 100 x100 THz FPA with a 150 x 150 {\mu}m pixel is designed, fabricated, and characterized. The dependence of the THz absorption ratio on the thickness of SiNx dielectric substrate film is investigated. The fabricated FPA exhibits a 90.6% resonant absorption at 1.36 THz, agreeing considerably with the theoretical simulation results. Our results imply that such a substrate-free THz focal plane metamaterial array enables the realization of THz imaging.

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Zhigang Li, Yi Ou, Xubiao Peng, Jianyu Fu, Wen Ou, Wenjing Jiang, Qing Zhao. 2020-11-27. Substrate-free THz focal plane metamaterial array with high absorption ratio. https://arxiv.org/abs/2012.03252

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