Open AccessTerahertz polarization-maintaining subwavelength filters
Author(s) -
Haisu Li,
Shaghik Atakaramians,
Jin Yuan,
Xijiang Han,
Wei Wang,
Yueqin Li,
Beilei Wu,
ZhongJie Han
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.025617
Subject(s) - terahertz radiation , optics , extinction ratio , polarization (electrochemistry) , grating , full width at half maximum , materials science , waveguide , optical filter , band pass filter , optoelectronics , physics , wavelength , chemistry
Terahertz (THz) polarization-maintaining waveguides, which have been considered fundamental elements in polarization-sensitive THz systems, are promising platforms in developing functional THz devices. Here, we propose a THz grating based on a subwavelength rectangular polymer waveguide, which filters two polarization states simultaneously. The proposed gratings are characterized and discussed using numerical simulations. We observe two transmission dips with over a 20.9 dB extinction ratio (ER) and around a 21.1 GHz full-width half-maximum (FWHM), where the reflective frequencies of the two polarization waves and the separation between them can be harnessed with appropriate structure designs. Furthermore, we demonstrate that the grating can operate as a polarization-maintaining narrow bandpass filter (ER>12.3 dB and FWHM<1.7 GHz) by introducing a π-phase shift. This work has the potential to open a new avenue for steering polarized THz radiation using the waveguide-based filters, which could be integrated in THz polarization-sensitive imaging, sensing, and wireless communication systems.