Quasi-Optical Terahertz Polarizers Enabled by Inkjet Printing of Carbon Nanocomposites

We report a new approach for cost-effective manufacturing of THz quasi-optical polarizers by inkjet printing of polymer-carbon nanowhisker (CNW) dispersions. The electromagnetic interference properties of coatings with fixed CNW/polymer composition and varying thickness are quantified by a frequency domain THz spectroscopy system in the range 570-630GHz. A shielding effectiveness of ~40dB is attained for 70m-thick coatings. A prototype THz polarizer printed on Mylar film displayed transmission and absorbance that varied with polarization orientation. The degree of polarization for film thickness of ~1μm was 0.35. This performance can be improved by refining grid dimensions, increasing coating thickness and adopting multi-layer polarizer structures.