Broadband polarization rotator based on multi-order plasmon resonances and high impedance surfaces

• Published in: Journal of applied physics Vol. 114; no. 7
• Main Authors: Feng, Mingde, Wang, Jiafu, Ma, Hua, Mo, Weidong, Ye, Hongjun, Qu, Shaobo
• Format: Journal Article
• Language: English
• Published: 21.08.2013
• Subjects: Broadband; Conversion; High impedance; Incident waves; Plasmons; Polarization; Reflected waves; Symmetry
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.4819017

We experimentally investigate the electromagnetic (EM) responses of a broadband reflective polarization rotator under normal incidence. It is found that the rotator can generate multi-order plasmon resonances at three neighboring frequencies. At each frequency, the rotator behaves as a high impedance surface along one axis while as a metallic reflective surface along the other axis. Thus, a 180° phase difference is generated between the two orthogonal components of reflected waves. When the incident wave is polarized by 45° with respect to the symmetry axis of the rotator, the polarization of reflected waves is rotated by 90°. The designed rotator presents broadband properties. It can perform perfect 90° polarization rotation at three frequencies and maintains a polarization conversion efficiency greater than 56% in 2.0–3.5 GHz. The rotator provides a route to broadband polarization rotation and has application values in polarization control.