Experimental verification of asymmetric transmission in continuous omega-shaped metamaterials

A bi-layer continuous omega-shaped metamaterial was proposed and fabricated to measure the asymmetric transmission (AT) effect of a linearly polarized light at near-infrared region. The metamaterial was fabricated by the electron-beam lithography method, and the AT effect was demonstrated by the difference between total transmittances in the two opposite propagation directions for x-/y-polarized incident light. The experimental results were confirmed by the full-wave simulated results. Importantly, we also experimentally demonstrated that the AT effect is robust against the misalignments between the first and the second omega-shaped layers. Accordingly, the successfully prepared sample and its characterization provide a bright future for applications in light-controlled switchers and optical diodes in on-chip optical systems and information communication systems.