Zhang Zhengren, Zhang Bingxue, He Qian, Han Ping, Xu Quan, Wu Chao
Opt Express. 2024 Oct 7;32(21):36674-36685. doi: 10.1364/OE.537765.
Orbital angular momentum (OAM) beams have demonstrated significant potential in the fields of communication, imaging and quantum information science. In particular, active OAM metasurfaces enable flexible and on-demand control of OAM beams without altering their structures, significantly enriching the applications of OAM beams. However, due to the limitations of electrode wiring and unit structure efficiency, most existing active metasurface designs are reflective, hindering the further development of this field. Here, we propose an active induced magnetism Huygens' metasurface to overcome these limitations. We demonstrate that transmissive and high-efficiency OAM mode reconfigurable beams of topological charge l = -1 or l = +1, as well as spatiotemporally modulated spinning OAM harmonic beam of topological charge l = +1 can be generated on-demand. The findings of this study provide a novel approach to achieve more flexible and diversified OAM beamforming, addressing the evolving demands of various OAM-related applications.
轨道角动量（OAM）光束在通信、成像和量子信息科学领域已展现出巨大潜力。特别是，有源OAM超表面能够在不改变光束结构的情况下灵活且按需地控制OAM光束，极大地丰富了OAM光束的应用。然而，由于电极布线和单元结构效率的限制，现有的大多数有源超表面设计都是反射型的，这阻碍了该领域的进一步发展。在此，我们提出一种有源感应磁性惠更斯超表面来克服这些限制。我们证明，可以按需生成拓扑电荷l = -1或l = +1的透射式高效OAM模式可重构光束，以及拓扑电荷l = +1的时空调制自旋OAM谐波光束。本研究的结果提供了一种实现更灵活、更多样化OAM波束形成的新方法，满足了各种与OAM相关应用不断变化的需求。
