Tsujimura Toru Ii, Goto Yuki, Okada Koji, Kobayashi Sakuji, Kubo Shin
National Institute for Fusion Science, National Institutes of Natural Sciences, Toki, Gifu 509-5292, Japan.
College of Engineering, Chubu University, Kasugai, Aichi 487-8501, Japan.
Rev Sci Instrum. 2022 Apr 1;93(4):043507. doi: 10.1063/5.0077893.
In this paper, we report the development of off-axis spiral phase mirrors that can be used to generate optical vortices from a range of millimeter waves. An obliquely incident Gaussian beam is reflected from a spiral phase mirror and is converted into an optical vortex beam with a desired topological charge. The mirrors were fabricated by mechanical machining. The designed vortex properties of reflected waves were investigated experimentally by using a low-power test, where the designed topological charge was verified based on the interference pattern between a vortex beam and a Gaussian-like beam. The designed topological charge was also estimated by using a phase retrieval method specialized for a vortex beam. These off-axis spiral phase mirrors can be used for propagation experiments of radio frequency waves with helical wavefronts in magnetized plasma.
在本文中，我们报告了离轴螺旋相位镜的研制情况，该相位镜可用于从一系列毫米波中产生光学涡旋。倾斜入射的高斯光束从螺旋相位镜反射后，被转换为具有所需拓扑电荷的光学涡旋光束。这些镜子是通过机械加工制造的。通过低功率测试对反射波的设计涡旋特性进行了实验研究，其中基于涡旋光束和类高斯光束之间的干涉图样验证了设计的拓扑电荷。还通过使用专门针对涡旋光束的相位恢复方法估计了设计的拓扑电荷。这些离轴螺旋相位镜可用于在磁化等离子体中进行具有螺旋波前的射频波传播实验。
