Laminated polarization splitter with a large split angle

A new spatial walk-off polarizer with a large polarization-splitting angle is fabricated. The polarizer, which utilizes artificial anisotropic dielectrics, is composed of layers of periodically laminated a-Si:H/SiO2 thin films. The thickness of each layer is 67 nm, while the total number of the layers amounts to 1440. The measured polarization-splitting angle is 15.5° at λ=1.55 μm, which is 2.7 times larger than that of existing polarizers.