LAUSR

Abstract We developed an ultrabroadband two-layer hybrid grating for polarizer. The efficiencies and extinction ratios of the two-layer polarizer were characterized for different grating geometrical parameters including periods, duty cycles and dielectric layer thicknesses. In order to obtain the suitable grating geometric parameters, the diffraction was numerically simulated by using rigorous coupled-wave approach in the near infrared incident regions. Based on the simulation results, reflection efficiency of TE-polarized light and transmission efficiency of TM-polarized light more than 96 % can be obtained within the incident wavelength rang of 1220−1940 nm and incident angle range of 4.2–58.8°. Furthermore, the extinction ratio of the grating can reach 28.09 dB for the polarizer.