Design and Measurement of a Terahertz Large-Aperture Quarter-Wave Plate with Double-layer Metal Cut Wires on a Flexible and Thin Film

Abstract

The polarization control of a terahertz wave can provide fruitful technology for communication, imaging, and exploration of novel phenomena in terahertz frequencies. However, it is not so easy to realize a high-performance wave plate with a large aperture, flexibility, and thinness at low cost and by easy fabrication. We design and fabricate a terahertz quarter-wave plate on a cyclo-olefin polymer film with a copper layer by etching. Measurements by terahertz time-domain spectroscopy confirm a transmission power with 82% and an ellipticity with -1.0 at 0.43 THz. The quarter-wave plate would lead to compact transmission devices and many progressive applications.