Dual-band asymmetric transmission of linear polarization in bilayered chiral metamaterial

A bilayered chiral metamaterial is proposed and demonstrated to exhibit dual-band asymmetric transmission of linearly polarized electromagnetic waves in two opposite directions. Simulated and measured results show that the bilayered chiral metamaterial can achieve cross-polarization conversion with an efficiency of over 90% for both y- and x-polarized waves. The proposed metasurface can be regarded as an ultrathin polarization-controlled switch that is easily switched on/off by changing a linearly polarized wave to its orthogonal component.