title: High extinction ratio and low transmission loss thin-film terahertz polarizer with a tunable bilayer metal wire-grid structure.
abstract: A thin-film terahertz polarizer is proposed and realized via a tunable bilayer metal wire-grid structure to achieve high extinction ratios and good transmission. The polarizer is fabricated on top of a thin silica layer by standard micro-fabrication techniques to eliminate the multireflection effects. The tunable alignment of the bilayer aluminum-wire grid structure enables tailoring of the extinction ratio and transmission characteristics. Using terahertz time-domain spectroscopy (THz-TDS), a fabricated polarizer is characterized, with extinction ratios greater than 50 dB and transmission losses below 1 dB reported in the 0.2-1.1 THz frequency range. These characteristics can be improved by further tuning the polarizer parameters such as the pitch, metal film thickness, and lateral displacement.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Huang
authors.forename: Edward P J
authors.initials: EP
authors.lastname: Parrott
authors.forename: Hongkyu
authors.initials: H
authors.lastname: Park
authors.forename: Hau Ping
authors.initials: HP
authors.lastname: Chan
authors.forename: Emma
authors.initials: E
authors.lastname: Pickwell-MacPherson