Open AccessCompact dual-band circular polarizer using twisted Hilbert-shaped chiral metamaterial
Author(s) -
HeXiu Xu,
Guangming Wang,
Mei Qi,
Tong Cai,
Tie Jun Cui
Publication year - 2013
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.21.024912
Subject(s) - polarizer , metamaterial , circular polarization , optics , physics , polarization (electrochemistry) , resonator , extinction ratio , circular dichroism , split ring resonator , optical rotation , birefringence , wavelength , microstrip , chemistry , crystallography
We propose a kind of chiral metamaterial inspired from the fractal concept. The Hilbert fractal perturbation in the twisted split ring resonator element results in compact metamaterial and breaking mirror symmetry, which readily forms chirality over triple bands. The discrepancy between co-polarization conversion and cross-polarization conversion over multiple bands can be explored for multifunctional devices. A multiband circular polarizer is then numerically and experimentally studied in the X band based on the bilayered twisted Hilbert resonator with mutual 90° rotation. The ability of transforming linearly polarized incident waves to circularly polarized waves is unambiguously demonstrated with high conversion efficiency and large polarization extinction ratio of more than 20 dB across dual bands. Moreover, exceptionally strong optical activity and circular dichroism are also observed.