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arXiv · 1711.08003

Electromechanically Tunable Metasurface Transmission Waveplate at Terahertz Frequencies

Xiaoguang Zhao·Jacob Schalch·Jingdi Zhang·Huseyin R. Seren·Guangwu Duan·Richard D. Averitt·Xin Zhang
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Abstract

Dynamic polarization control of light is essential for numerous applications ranging from enhanced imaging to materials characterization and identification. We present a reconfigurable terahertz metasurface quarter-waveplate consisting of electromechanically actuated micro-cantilever arrays. Our anisotropic metasurface enables tunable polarization conversion cantilever actuation. Specifically, voltage-based actuation provides mode selective control of the resonance frequency, enabling real-time tuning of the polarization state of the transmitted light. The polarization tunable metasurface has been fabricated using surface micromachining and characterized using terahertz time domain spectroscopy. We observe a ~230 GHz cantilever actuated frequency shift of the resonance mode, sufficient to modulate the transmitted wave from pure circular polarization to linear polarization. Our CMOS-compatible tunable quarter-waveplate enriches the library of terahertz optical components, thereby facilitating practical applications of terahertz technologies.

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Xiaoguang Zhao, Jacob Schalch, Jingdi Zhang, Huseyin R. Seren, Guangwu Duan, Richard D. Averitt, Xin Zhang. 2017-11-21. Electromechanically Tunable Metasurface Transmission Waveplate at Terahertz Frequencies. https://doi.org/10.1364/optica.5.000303

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