Abstract

Thin terahertz (THz) -wave optical components are essentially required in integrated THz-wave spectroscopy and imaging systems [1,2]. Generally, not only transmission in amplitude but also phase control are significant on manipulations of wave propagation. In this paper, we report a thin THz-wave phase shifter demonstrated by flexible film metamaterial with high transmission. The device design has two parts, where one works as a phase shifter of 1/4 π and the other works as the reference for the phase shifter. Metamaterial unit structure employs double-layer split ring resonators (SRRs) both for the two parts to obtain the relative phase difference of 1/4 π while keeping the same transmission coefficient of 0.82. The phase shifter also holds the property of polarization independence due to the four-fold symmetry on the SRR structure. The device is developed by photolithography and wet etching techniques with flexible polymer film used as the substrate.

© 2017 Japan Society of Applied Physics, Optical Society of America