High-efficiency generation of circularly polarized light via symmetry-induced anomalous reflection

• Published in: Physical review. B, Condensed matter and materials physics Vol. 91; no. 12
• Main Authors: Jiang, Shang-Chi, Xiong, Xiang, Hu, Yuan-Sheng, Jiang, Sheng-Wei, Hu, Yu-Hui, Xu, Di-Hu, Peng, Ru-Wen, Wang, Mu
• Format: Journal Article
• Language: English
• Published: 16-03-2015
• Subjects: Beams (radiation); Circularity; Condensed matter; Incident light; Polarization; Polarized light; Reflection; Silicon dioxide
• ISSN: 1098-0121; 1550-235X
• DOI: 10.1103/PhysRevB.91.125421

Great efforts have been devoted to control the polarization state, the transmission direction, and the phase of light within a very confined space in recent decades. Here, we present a two-dimensional metastructure made of an array of unisized split rings with different opening orientations on the surface of a SiO sub(2)-silver bilayer. This structure possesses an unexpectedly high polarization conversion ratio and generates significantly strong anomalous reflection beams (over 70% of incident light intensity) over a broad frequency range (1100-1750 nm). Functionally, it is able to turn either a linearly polarized incident light or natural light into two perfect circularly polarized beams with the same amplitude yet different handedness to different directions. These features demonstrate a clear example of momentum conservation and can be applied to detect/manipulate the propagation of circularly polarized light.