Herein, we fabricated and investigated the carbon nanotube (CNT) integrated metamaterial for orthogonal polarization control in the THz regime, which is composed of a sandwiched CNT layer with the adjacent metal gratings in the sub-wavelength integration. Under the mechanism of multilayer polarization selection and multiple reflections in CNT constructed micro-cavity, the perfect orthogonal polarization conversion is achieved and the transmittance spectrum presents multi-band peaks and valleys, which coincide with the theoretical Fabry-Perot resonance. Besides, by controlling the layer number and orientations of the middle CNT, the active modulation of the amplitude and phase in compound metamaterials are realized. Based on the simulation of CNT in the grating model, it obtains a good agreement with the experimental results, and the simulated electric field distribution also confirmed the inner polarization conversion mechanism. This work combines nanomaterials with optical microstructures and successfully applies them to the THz polarization control, which will bring new ideas for design novel THz devices.

中文翻译：

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基于碳纳米管集成超材料的多频带太赫兹线性极化转换器

在这里，我们制造并研究了在THz范围内用于正交极化控制的碳纳米管（CNT）集成超材料，该材料由夹在中间的CNT层与亚波长集成中的相邻金属光栅组成。在CNT构造的微腔中选择多层偏振并进行多次反射的机制下，实现了完美的正交偏振转换，并且透射光谱呈现出多波段的峰和谷，与理论Fabry-Perot共振相符。此外，通过控制中间CNT的层数和方向，可以实现复合超材料中振幅和相位的主动调制。基于碳纳米管在光栅模型中的仿真，与实验结果吻合良好，模拟的电场分布也证实了内部极化转换机制。这项工作将纳米材料与光学微结构相结合，并将其成功地应用于太赫兹偏振控制，这将为设计新颖的太赫兹器件带来新的思路。