In this Letter, we report the design, analysis, and characterization of first- and second-order plasmonic metamaterial-based multi-mode filtering structures. Further, electronic adaptivity in filter transfer functions is introduced and characterized. First, the basic operating principle of the engineered multi-mode resonator-based bandpass filter is presented. Then the concept is extended by introducing electronic (dynamic) tuning of the bandwidth using semiconductor varactor diodes. Afterwards, to enhance the selectivity and out-of-band filtering response, second-order multi-mode designs are realized. For experimental verification, the hardware prototype is fabricated and characterized using the Keysight analyzer N9918A. The design filtering structures will pave an important role in tunable plasmonic circuits and systems.

中文翻译：

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具有动态可调性的基于等离子超材料的滤波结构

在这封信中，我们报告了基于一阶和二阶等离子体超材料的多模滤波结构的设计，分析和表征。此外，介绍并表征了滤波器传递函数中的电子适应性。首先，介绍了基于工程多模谐振器的带通滤波器的基本工作原理。然后，通过使用半导体变容二极管引入带宽的电子（动态）调整来扩展该概念。然后，为了提高选择性和带外滤波响应，实现了二阶多模式设计。为了进行实验验证，使用是德科技分析仪N9918A制造并表征了硬件原型。设计滤波结构将在可调谐等离子体电路和系统中扮演重要角色。