Abstract Broadband control of polarization state is essential for terahertz applications ranging from non-destructive testing to imaging in medicine and wireless communications. We present a single-layered terahertz anisotropic metasurface quarter-wave plate consisting of hybrid metallic wire grating arrays, which enables broadband linear to pure circular polarization conversion with an ellipticity over 0.99 and 43% bandwidth of the central wavelength. The broadband effect is robust across a wide range of incident angles. Interestingly, Angle-tunable arbitrary polarization states are implemented by changing the angle of incidence at other frequencies. Such single-layered broadband quarter-wave plate provides a route to develop broadband polarization conversion components, facilitating compact applications of terahertz technologies.

中文翻译：

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基于单层各向异性太赫兹超表面的宽带广角四分之一波片

摘要 偏振态的宽带控制对于从无损检测到医学成像和无线通信的太赫兹应用至关重要。我们提出了一种由混合金属线光栅阵列组成的单层太赫兹各向异性超表面四分之一波片，它能够实现宽带线性到纯圆偏振转换，椭圆率超过 0.99 和中心波长的 43% 带宽。宽带效应在很宽的入射角范围内都是稳健的。有趣的是，角度可调的任意偏振态是通过改变其他频率的入射角来实现的。这种单层宽带四分之一波片为开发宽带偏振转换组件提供了一条途径，促进了太赫兹技术的紧凑应用。