Optical vortex beams carrying orbit angular momentum have attracted significant attention recently. Perfect vortex beams, characterized by their topological charge-independent intensity profile, have important applications in enhancing communication capacity and optimizing particle manipulation. In this paper, metal-insulator-metal copper-coin type reflective metasurfaces are proposed to generate perfect composite vortex beams in X-band. We introduce the qualified equivalent circuit model based on the theory of transmission line to design the meta-atom of the structure. The experiments are performed to measure the far-field and near-field perfect composite vortex beams and evaluate their orbital angular momentum purity at different frequencies. The experimental results agree well with the theoretical predictions. This work provides new ideas and methods for generating high-quality metasurface-based perfect composite vortex beams in the microwave region, paving an ideal path for microwave communication systems, optical manipulation and radar detection.

中文翻译：

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微波波段具有反射超表面的高效完美复合涡旋光束的测量


近年来，携带轨道角动量的光学涡旋光束引起了人们的广泛关注。完美的涡旋光束以其拓扑电荷无关的强度分布为特征，在增强通信能力和优化粒子操纵方面具有重要应用。本文提出了金属-绝缘体-金属铜-硬币型反射超表面，以产生完美的 X 波段复合涡旋光束。我们基于传输线理论引入了合格的等效电路模型来设计结构的超原子。通过实验测量了远场和近场完美复合涡旋光束，并评估了它们在不同频率下的轨道角动量纯度。实验结果与理论预测吻合较好。这项工作为在微波区域生成高质量的基于超表面的完美复合涡旋光束提供了新的思路和方法，为微波通信系统、光学操纵和雷达探测铺平了一条理想的道路。