Ahmed Hammad, Intaravanne Yuttana, Ming Yang, Ansari Muhammad Afnan, Buller Gerald S, Zentgraf Thomas, Chen Xianzhong
Institute of Photonics and Quantum Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
School of Electronic and Information Engineering, Changshu Institute of Technology, Suzhou, 215000, China.
Adv Mater. 2022 Jul;34(30):e2203044. doi: 10.1002/adma.202203044. Epub 2022 Jun 17.
Inspired by plant grafting, grafted vortex beams can be formed through grafting two or more helical phase profiles of optical vortex beams. Recently, grafted perfect vortex beams (GPVBs) have attracted much attention due to their unique optical properties and potential applications. However, the current method to generate and manipulate GPVBs requires a complex and bulky optical system, hindering further investigation and limiting its practical applications. Here, a compact metasurface approach for generating and manipulating GPVBs in multiple channels is proposed and demonstrated, which eliminates the need for such a complex optical setup. A single metasurface is utilized to realize various superpositions of GPVBs with different combinations of topological charges in four channels, leading to asymmetric singularity distributions. The positions of singularities in the superimposed beam can be further modulated by introducing an initial phase difference in the metasurface design. The work demonstrates a compact metasurface platform that performs a sophisticated optical task that is very challenging with conventional optics, opening opportunities for the investigation and applications of GPVBs in a wide range of emerging application areas, such as singular optics and quantum science.
受植物嫁接的启发，通过嫁接两个或多个光学涡旋光束的螺旋相位分布可以形成嫁接涡旋光束。近年来，嫁接完美涡旋光束（GPVBs）因其独特的光学特性和潜在应用而备受关注。然而，目前产生和操纵GPVBs的方法需要一个复杂且庞大的光学系统，这阻碍了进一步的研究并限制了其实际应用。在此，提出并演示了一种用于在多个通道中产生和操纵GPVBs的紧凑型超表面方法，该方法无需如此复杂的光学设置。利用单个超表面在四个通道中实现具有不同拓扑电荷组合的GPVBs的各种叠加，从而导致不对称奇点分布。通过在超表面设计中引入初始相位差，可以进一步调制叠加光束中奇点的位置。这项工作展示了一个紧凑型超表面平台，该平台执行一项用传统光学方法极具挑战性的复杂光学任务，为GPVBs在奇异光学和量子科学等广泛的新兴应用领域的研究和应用开辟了机会。
