Yirmiyahu Yaniv, Niv Avi, Biener Gabriel, Kleiner Vladimir, Hasman Erez
Optical Engineering Laboratory, Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Opt Lett. 2006 Nov 15;31(22):3252-4. doi: 10.1364/ol.31.003252.
Transformation and inverse transformation between a free-space linearly polarized beam and the vectorial vortex mode of a circular hollow waveguide by use of Pancharatnam-Berry phase optical elements is proposed. Demonstration was achieved by fabricating GaAs subwavelength gratings and utilizing a 300 microm diameter hollow metallic waveguide for 10.6 microm wavelength CO(2) laser radiation. The mode transformations and the excitation of a single vectorial mode inside the hollow waveguide were verified by full polarization measurements. In addition, the inverse mode transformation of the single vectorial mode excitation in the waveguide enabled us to experimentally obtain a linearly polarized bright spot with a high central lobe.
提出了利用潘查拉特纳姆-贝里相位光学元件在自由空间线偏振光束与圆形空心波导的矢量涡旋模式之间进行变换和逆变换。通过制作砷化镓亚波长光栅并利用直径为300微米的空心金属波导来传输10.6微米波长的CO₂激光辐射实现了演示。通过全偏振测量验证了空心波导内的模式变换和单个矢量模式的激发。此外，波导中单个矢量模式激发的逆模式变换使我们能够通过实验获得具有高中心瓣的线偏振亮点。
