A broadband multi‐functional bi‐switchable ultrathin optical metamaterial design is investigated, which can achieve a high polarization conversion efficiency over a wide band of frequencies in the terahertz (THz) regime. The proposed design switches from a linear and circular polarization converter (LPC/CPC) to an efficient absorber by using the phase change property of a functional material, vanadium dioxide (VO2). The proposed design shows switching from an absorber to a reflector using the mechanical configuration of the functional material, and therefore the design can be used as a bi‐switchable device. The first type of switching is accomplished by changing the conductivity of the functional material, while the second type of switching is achieved with the help of the mechanical configuration of the functional material. Moreover, the structure is responsive to wide incident angles. The proposed switchable design has the potential to contribute to the development of tunable polarization rotating devices and on/off switching LPC devices, which have wide applications in detection, sensing, and communications.

中文翻译：

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用于太赫兹偏振调制的超薄双开关二氧化钒基多功能超材料


研究了宽带多功能双开关超薄光学超材料设计，它可以在太赫兹（THz）范围内的宽频带上实现高偏振转换效率。所提出的设计利用功能材料二氧化钒 (VO2) 的相变特性，从线性和圆偏振转换器 (LPC/CPC) 切换为高效吸收器。所提出的设计显示了使用功能材料的机械配置从吸收器切换到反射器，因此该设计可以用作双切换器件。第一种类型的转换是通过改变功能材料的电导率来实现的，而第二种类型的转换是借助功能材料的机械构造来实现的。此外，该结构对宽入射角敏感。所提出的可切换设计有可能有助于可调谐偏振旋转器件和开/关切换 LPC 器件的开发，这些器件在检测、传感和通信领域具有广泛的应用。