Electroelastic metasurface with resonant piezoelectric shunts for tunable wavefront control
Electroelastic metasurface with resonant piezoelectric shunts for tunable wavefront control
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DOI：
10.1088/1361-6463/acbd5f
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发表时间：
2022-12
期刊：
影响因子：
--
通讯作者：
Z. Lin;S. Tol
中科院分区：
文献类型：
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作者：
Z. Lin;S. Tol
在本文中，我们设计了一种由周期性分布的压电贴片和谐振型并联电路组成的可调谐相位调制超表面。电弹性超表面由于其亚波长特性，可以在较小的占地面积内控制最低反对称模式兰姆波（A 0 模式）的波前。建立全耦合机电模型来研究超表面单元的传输特性，并通过数值和实验研究进行验证。基于对超表面单元的分析，我们首先探索具有单谐振分流器的电弹性超表面的性能，然后通过多谐振分流器扩展其能力。通过仅调节并联电路中的电负载，我们利用所提出的超表面分别实现不同角度和焦点的A 0 模式兰姆波的波偏转和波聚焦。数值模拟表明，具有单谐振分流器的超表面可以将 5 kHz 和 6 kHz 弯曲波的波前偏转所需角度，偏差小于 2%。此外，它还可以进行调整，以在-75∘到75∘的广泛角度范围内，在设计的焦点处实现近三倍的位移放大。此外，通过多谐振分流器，基于压电的超表面可以实现对多个频率（即同时在5 kHz和10 kHz）弯曲波的反常波控制，为广泛的工程应用开发新的潜力，例如解复用各种频率分量或将它们引导和聚焦在不同的位置。
In this paper, we design a tunable phase-modulated metasurface composed of periodically distributed piezoelectric patches with resonant-type shunt circuits. The electroelastic metasurface can control the wavefront of the lowest antisymmetric mode Lamb wave (A 0 mode) in a small footprint due to its subwavelength features. The fully coupled electromechanical model is established to study the transmission characteristics of the metasurface unit and validated through numerical and experimental studies. Based on the analysis of the metasurface unit, we first explore the performance of electroelastic metasurface with single-resonant shunts and then extend its capability with multi-resonant shunts. By only tuning the electric loads in the shunt circuits, we utilize the proposed metasurface to accomplish wave deflection and wave focusing of A 0 mode Lamb waves at different angles and focal points, respectively. Numerical simulations show that the metasurface with single-resonant shunts can deflect the wavefront of 5 kHz and 6 kHz flexural waves by desired angles with less than 2% deviation. In addition, it can be tuned to achieve nearly three times displacement amplification at the designed focal point for a wide range of angles from −75∘ to 75∘. Furthermore, with multi-resonant shunts, the piezoelectric-based metasurface can accomplish anomalous wave control over flexural waves at multiple frequencies (i.e. simultaneously at 5 kHz and 10 kHz), developing new potentials toward a broad range of engineering applications such as demultiplexing various frequency components or guiding and focusing them at different positions.