A perfect metamaterial polarization rotator

作者:Cong, Longqing; Cao, Wei; Zhang, Xueqian; Tian, Zhen; Gu, Jianqiang; Singh, Ranjan; Han, Jiaguang*; Zhang, Weili
来源:Applied Physics Letters, 2013, 103(17): 171107.
DOI:10.1063/1.4826536

摘要

Polarization conveys valuable information for electromagnetic signal processing exhibiting tremendous potential in developing application driven photonic devices. Manipulation of polarization state of an electromagnetic wave has drawn a lot of research interests in many different fields, especially in the terahertz regime. Here, we propose a unique approach to efficiently rotate the linear polarization of terahertz wave in a broadband configuration with tri-layer metasurfaces. We experimentally observe a nearly perfect orthogonal polarization conversion with an ultrahigh efficiency, demonstrating a ultrathin terahetz rotator. The Fabry-Perot cavity effect in the tri-layer metasurfaces is attributed to the underlying mechanism of high transmittance and polarization rotation.