Open AccessLarge asymmetric anomalous reflection in bilayer gradient metasurfaces
Author(s) -
Guohua Dong,
Zhongjiao Jiang,
Yicheng Li,
Zheng Zhu,
Tingting Lv,
Mengke Sun,
Bo Lv,
Yuxiang Li,
Chunying Guan,
Zhihai Liu,
Jinhui Shi
Publication year - 2021
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.425987
Subject(s) - optics , reflection (computer programming) , bilayer , wavefront , nanorod , polarization (electrochemistry) , refractive index , materials science , physics , nanotechnology , chemistry , membrane , biology , computer science , genetics , programming language
Gradient metasurfaces have attracted much attention due to intriguing wavefront and polarization manipulation. Here, a bilayer gradient metasurface is constructed by use of a rectangular nanorod layer and its complementary nanoaperture. It reveals asymmetric anomalous reflection and symmetric anomalous transmission for two counter-propagating directions. The dependence of the anomalous reflection and transmission phenomena on nanostructure thickness are numerically studied in optical frequencies. The increasing metallic layer thickness of the gradient metasurface greatly enhances anomalous reflection of the left-handed circularly polarized wave (LCP) for the nanorod side and suppresses anomalous reflection for the other side. Both resonant frequencies of anomalous reflection and transmission linearly shift with the refractive index. The bilayer gradient metasurface is important for realizing wavefront modulation and optical sensing.