A simple method that is compatible with all geometrical structures of terahertz (THz) metamaterials for increasing their frequency tunabilities and decreasing their operating electric fields is proposed. This method uses the displacement of glycerol droplets with various volumes to tune the resonance frequency of a THz metamaterial in an electrowetting-on-dielectric (EWOD) cell. The experimental results reveal that the THz metamaterial has a large frequency tunability of 28% at an operating electric field that is smaller than 0.2 V/µm as the glycerol droplets move in and out of the path of a THz beam. The frequency tunability is large because the near field of the metamaterial “experiences” a large difference between the refractive indices of glycerol and air. The EWOD cell with the THz metamaterial is a great achievement for developing electrically controllable band-stop filters with large frequency tunabilities and small operating electric fields.

中文翻译：

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使用电介质上的电润湿电池具有大可调性和低工作电场的电可控太赫兹超材料

提出了一种与太赫兹 (THz) 超材料的所有几何结构兼容的简单方法，以增加其频率可调性并降低其工作电场。该方法使用不同体积的甘油液滴的位移来调整电介质上电润湿 (EWOD) 单元中太赫兹超材料的共振频率。实验结果表明，当甘油液滴进出太赫兹光束的路径时，太赫兹超材料在小于 0.2 V/μm 的工作电场下具有 28% 的大频率可调性。频率可调性很大，因为超材料的近场“经历”了甘油和空气折射率之间的巨大差异。