Open AccessAchromatic wave plate in THz frequency region based on parallel metal plate waveguides with a pillar array
Author(s) -
Masaya Nagai,
Noriyuki Mukai,
Yosuke Minowa,
Masaaki Ashida,
Takao Suzuki,
Jun Takayanagi,
Hideyuki Ohtake
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.004641
Subject(s) - optics , achromatic lens , terahertz radiation , materials science , waveplate , birefringence , transverse plane , surface wave , extraordinary optical transmission , optoelectronics , surface plasmon , surface plasmon polariton , physics , laser , plasmon , structural engineering , engineering
We demonstrated an achromatic wave plate based on parallel metal plate waveguides in the high THz frequency region. The metal plates have periodic rough structures on the surface, which allow slow transverse magnetic wave propagation and fast transverse electric wave propagation. A numerical simulation showed that the height of the periodic roughness is important for optimizing the birefringence. We fabricated stacked metal plates containing two types of structures by chemical etching. An array of small pillars on the metal plates allows higher frequency optimization. We experimentally demonstrated an achromatic quarter-wave plate in the frequency region from 2.0 to 3.1 THz.