The Application of the Sawtooth Photonic Crystal on Producing Polarized Light

We have proposed a sawtooth photonic crystal formed by Si-SiO₂ periodic layers designed on a planar medium as a polarizer. The polarizer can produce H-polarized light very efficiently because the frequency of E-polarized light is chosen at the photonic band gap but that of H-polarized light at the photonic conduction band. The best polarization ratio is as high as 2.56 × 10⁵ : 1 when the normalized frequency α/λ is 0.24 and the incident angle is about 13°. Highly polarized light can be produced in a normalized frequency range from 0.23 to 0.25, and this can possibly be applied to an LED with a certain bandwidth.