Polarization-controlled grating polarizer under second Bragg incidence with silver deposited in groove

Under the second Bragg incidence, a new polarization-controlled grating is proposed based on the multilayer dielectric grating structure. This novel polarizing beam splitter can diffract TE wave in the 0th order and TM wave in the -1st/-2nd orders. In most reported polarization-selective dual-function beam splitter, two polarizations cannot be separated in the -1st order. While in this paper, as a polarizer, TE polarization and TM polarization propagate in different orders. At an incident wavelength of 800 nm, the efficiency of TE-polarized light is 99.32%. Both orders of TM-polarized light are more than 40%, and the extinction ratio is greater than 20 dB. This new high-efficiency polarizer can be used well in biosensors and optical communications.