Wang Dacheng, Gu Yinghong, Gong Yandong, Qiu Cheng-Wei, Hong Minghui
Opt Express. 2015 May 4;23(9):11114-22. doi: 10.1364/OE.23.011114.
Metamaterials promise an exotic approach to artificially manipulate the polarization state of electromagnetic waves and boost the design of polarimetric devices for sensitive detection, imaging and wireless communication. Here, we present the design and experimental demonstration of an ultrathin (0.29λ) terahertz quarter-wave plate based on planar babinet-inverted metasurface. The quarter-wave plate consisting of arrays of asymmetric cross apertures reveals a high transmission of 0.545 with 90 degrees phase delay at 0.870 THz. The calculated ellipticity indicates a high degree of polarization conversion from linear to circular polarization. With respect to different incident polarization angles, left-handed circular polarized light, right-handed circular polarized light and elliptically polarized light can be created by this novel design. An analytical model is applied to describe transmitted amplitude, phase delay and ellipticitiy, which are in good agreement with the measured and simulated results. The planar babinet-inverted metasurface with the analytical model opens up avenues for new functional terahertz devices design.
超材料有望提供一种奇特的方法来人工操纵电磁波的偏振态，并推动用于灵敏检测、成像和无线通信的偏振器件的设计。在此，我们展示了一种基于平面巴比涅倒置超表面的超薄（0.29λ）太赫兹四分之一波片的设计与实验演示。由不对称十字孔阵列组成的四分之一波片在0.870太赫兹处具有0.545的高透射率以及90度的相位延迟。计算得到的椭圆率表明从线偏振到圆偏振的高度偏振转换。对于不同的入射偏振角，这种新颖的设计可以产生左旋圆偏振光、右旋圆偏振光和椭圆偏振光。应用一个解析模型来描述透射幅度、相位延迟和椭圆率，其与测量结果和模拟结果吻合良好。具有该解析模型的平面巴比涅倒置超表面为新型功能性太赫兹器件的设计开辟了道路。
