Subwavelength high-performance polarizers in the deep ultraviolet region.

ABSTRACT

This study shows that high-performance metasurface polarizers are possible in the deep ultraviolet (DUV) region. A metasurface consisting of a trilayer of an Al (Aluminum) grating, an Al2O3 (Alumina) thin film, and an Al thin film serves as a mirror with high reflectance for light with polarization parallel to the grooves. The reflectance for polarization perpendicular to the grooves vanishes owing to destructive interference between the propagating and gap surface plasmon polaritons. As a result, the metasurface plays the role of a polarizer with a high extinction ratio exceeding 6.2 × 106. This study also shows that the bandwidth is improved by adjusting the incident angle, period, and the Al2O3 layer of the metasurface. The performance of the metasurface polarizer is discussed experimentally. Our finding paves the way for realizing high-performance polarizers in the DUV region.