Metamaterials can achieve superior electromagnetic properties over natural materials by adjusting the structure of the meta-atoms. Chiral metamaterials have been widely used in circular dichroism (CD) spectra, polarization imaging, and optical sensing. Here we propose a kind of all-silicon coding metasurfaces to achieve the function similar to chirality by spin decoupling. One of the two circularly polarized (CP) channels is scattered randomly, and the desired function is only designed in the other opposite CP channel. Three kinds of coding metasurfaces are designed to verify the reliability of such approach: one simultaneously possessing dual function of transmitting directly and scattering randomly, one capable of generating the superposition state of vortex beam, and the other generating the Bessel vortex beam, respectively. And some experimental verifications are carried out. This scheme is simpler and more versatile than previous schemes which require elaborate designed structure of the meta-atoms. Our novel approach provides a new option for implementing tunable chirality.

中文翻译：

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基于太赫兹带自旋解耦的全介电手性编码超表面

通过调整超原子的结构，超材料可以实现优于天然材料的电磁性能。手性超材料已被广泛用于圆二色性（CD）光谱，偏振成像和光学传感。在这里，我们提出了一种全硅编码的超表面，以通过自旋解耦实现类似于手性的功能。两个圆极化（CP）通道之一随机​​散布，并且仅在另一个相对的CP通道中设计了所需功能。设计了三种编码超表面来验证这种方法的可靠性：一种同时具有直接传输和随机散射的双重功能，一种能够生成涡旋光束的叠加状态，另一种分别生成贝塞尔涡旋光束。并进行了一些实验验证。该方案比以前的方案更简单，更通用，前者需要精心设计的亚原子结构。我们新颖的方法为实现可调手性提供了新的选择。