Due to its high electrical conductivity and excellent transmittance at terahertz frequencies, graphene is a promising candidate as transparent electrodes for terahertz devices. We demonstrate a liquid crystal based terahertz phase shifter with the graphene films as transparent electrodes. The maximum phase shift is 10.8 degree and the saturation voltage is 5 V with a 50 um liquid crystal cell. The transmittance at terahertz frequencies and electrical conductivity depending on the number of graphene layer are also investigated. The proposed phase shifter provides a continuous tunability, fully electrical controllability, and low DC voltage operation.
@article{arxiv.1309.1595,
title = {Graphene/liquid crystal based terahertz phase shifters},
author = {Yang Wu and Xuezhong Ruan and Chih-Hsin Chen and Young Jun Shin and Youngbin Lee and Jing Niu and Jingbo Liu and Yuanfu Chen and Kun-Lin Yang and Xinhai Zhang and Jong-Hyun Ahn and Hyunsoo Yang},
journal= {arXiv preprint arXiv:1309.1595},
year = {2013}
}