An electrically tunable terahertz (THz) plasmonic device is designed and fabricated using liquid metals (eutectic gallium indium) and shape memory alloy wires (Flexinol). The liquid metal is injected into the voids of a poly(dimethyl) siloxane microfluidic mold forming a periodic array of subwavelength apertures, while the wires are inserted into the elastomer below the metal plane. When a DC voltage is applied to the wires, they contract via Joule heating, reducing the aperture periodicity and blueshifting the transmission resonances of the device. When the voltage is removed, the wires cool and elongate back to their original length, allowing the transmission spectrum to return to its original state. The magnitude of this change depends upon the applied voltage. The device is shown to thermally cycle between the relaxed state and the fully contracted state reproducibly over at least 500 thermal cycles. The asymmetric geometry of the device and the contraction process yield transmission properties that are unexpected: two closely spaced resonances, where both resonances correspond to the same scattering indices, and an increase in the transmission amplitude of the lowest order resonance upon contraction. Numerical simulations are used to understand these features.

中文翻译：

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基于形状记忆合金和液态金属的电可调太赫兹等离子体设备

使用液态金属（共晶镓铟）和形状记忆合金线（Flexinol）设计和制造了一种电可调太赫兹（THz）等离子体激元器件。将液态金属注入聚（二甲基）硅氧烷微流体模具的空隙中，形成亚波长孔的周期性阵列，同时将导线插入金属平面下方的弹性体中。将直流电压施加到导线时，它们会通过焦耳加热而收缩，从而减小孔径周期性并使设备的传输谐振发生蓝移。去除电压后，导线冷却并伸长回原来的长度，从而使传输频谱恢复到原来的状态。这种变化的幅度取决于施加的电压。示出该装置在至少500个热循环上可再现地在松弛状态和完全收缩状态之间进行热循环。装置的不对称几何形状和收缩过程产生出乎意料的传输特性：两个紧密间隔的共振，其中两个共振对应于相同的散射指数，以及收缩时最低阶共振的透射幅度增加。数值模拟用于了解这些功能。收缩时最低阶共振的透射幅度增加。数值模拟用于了解这些功能。收缩时最低阶共振的透射幅度增加。数值模拟用于了解这些功能。