Metamaterial-based Design for a Half Wavelength Plate in the Terahertz Range

In this work a new design aimed to perform as a half-wavelength plate in the terahertz regime is presented. The fabricated samples exhibit a phase difference of 180 degrees at 0.73 THz between the two principal polarizations that matches with the modelling results. The experimentally determined transmittances of the two polarisations were around 61%, which is below theoretical predictions of reaching more than 90%. The difference between the two results is explained and possibilities for increasing the transmittance are presented.