A high extinction ratio plasmonic SU-8 waveguide polarizer

Abstract In this paper, a novel method has been proposed for increasing the extinction ratio of a plasmonic waveguide polarizer. Aluminum was coated in a 20-micron multi-strip pattern on the top of a SU-8 waveguide to excite the surface plasmons. The simulation and experimental results showed that the extinction ratio of the multi-strip polarizer was more than those of single-strip polarizers with the same total aluminum-coated length due to the coupling loss between the Al-coated and uncoated regions and also the scattering at the edge of metal. This polarizer was characterized over a wide range of wavelengths and showed the high extinction ratios of 46 dB and 26.8 dB at the wavelengths of 1550 nm and 980 nm, respectively.