In spite of the extensive studies of zero-index metamaterials, the realization of zero impedance with finite phase velocity has not been explored. Here, we show that this extreme case, realized by elaborately-tuned paired resonators, can effectively enhance sensing and actuation. To explain the formation mechanism of the near-zero effective impedance with finite phase velocity by paired resonators at a target frequency, a theory using an equivalent model based on mechanical longitudinal waves is developed. If the frequency of the extreme property is further tuned at a Fabry-Pérot resonance frequency, highly efficient enhancement is possible. Experiments using a piezoceramic transducer (PZT) installed on the plate region bounded by two resonators confirm that the proposed extreme property mechanism highly enhances the sensing and actuation outputs of the transducer.

中文翻译：

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具有有限相速度的近零有效阻抗，可通过谐振器配对增强传感和驱动。

尽管对零折射率超材料进行了广泛的研究，但尚未探索以有限相速度实现零阻抗。在这里，我们表明，通过精心调整的成对谐振器实现的这种极端情况可以有效增强传感和驱动。为了解释成对谐振器在目标频率下具有有限相速度的近零有效阻抗的形成机制，提出了一种使用基于机械纵波的等效模型的理论。如果将极端特性的频率进一步调整到法布里-珀罗共振频率，则可以实现高效增强。使用安装在由两个谐振器界定的板区域上的压电陶瓷换能器（PZT）进行的实验证实，所提出的极端特性机制极大地增强了换能器的传感和驱动输出。