Elliptical Hollow Fiber With Inner Silver Coating for Linearly Polarized Terahertz Transmission

Silver-coated elliptical hollow polycarbonate fibers for transmission of linearly polarized terahertz (THz) radiation are fabricated and characterized. A polarization ratio of 90% and a transmission loss of 0.79 dB/m at 0.65 THz are obtained for a 290-mm long fiber with major and minor inner radii of 2.42 and 1.18 mm. Modal birefringence in the order of 10
^-3
-10
^-2
is predicted in the frequency region of 0.3-1.5 THz. We also investigate the transmission characteristics of deformed fibers and found that the fiber with a semicircle cross section could rotate the direction of a linear polarization.