Abstract

A terahertz (THz) broadband polarizer using bilayer subwavelength metal wire-grid structure on both sides of polyimide film is simulated by the finite-difference time-domain method. We analyze the effect of film ­thickness, material loss, and lateral shift between two metallic gratings on the performance of the THz ­polarizer. Bilayer wire-grid polarizers are fabricated by a simple way of laser induced and non-electrolytic plating with copper. The THz time-domain spectroscopy measurements show that in 0.2-1.6 THz frequency range, the extinction ratio is better than 45 dB, the average extinction ratio reaches 53 dB, and the ­transmittance exceeds 67%, which shows great advantage over conventional single wire-grid THz polarizer.

© 2015 Chinese Optics Letters

High extinction ratio and low transmission loss thin-film terahertz polarizer with a tunable bilayer metal wire-grid structure

Zhe Huang, Edward P. J. Parrott, Hongkyu Park, Hau Ping Chan, and Emma Pickwell-MacPherson
Opt. Lett. 39(4) 793-796 (2014)

Bilayer Al wire-grids as broadband and high-performance polarizers

Yasin Ekinci, Harun H. Solak, Christian David, and Hans Sigg
Opt. Express 14(6) 2323-2334 (2006)

Terahertz wire-grid polarizers with micrometer-pitch Al gratings

Itsunari Yamada, Keisuke Takano, Masanori Hangyo, Mitsunori Saito, and Wataru Watanabe
Opt. Lett. 34(3) 274-276 (2009)

Flexible terahertz wire grid polarizer with high extinction ratio and low loss

A. Ferraro, D. C. Zografopoulos, M. Missori, M. Peccianti, R. Caputo, and R. Beccherelli
Opt. Lett. 41(9) 2009-2012 (2016)

Metal-film subwavelength-grating polarizer with low insertion losses and high extinction ratios in the terahertz region

Kazuo Shiraishi and Kengo Muraki
Opt. Express 23(13) 16676-16681 (2015)