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arXiv · 1309.1595

Graphene/liquid crystal based terahertz phase shifters

Yang Wu·Xuezhong Ruan·Chih-Hsin Chen·Young Jun Shin·Youngbin Lee·Jing Niu·Jingbo Liu·Yuanfu Chen·Kun-Lin Yang·Xinhai Zhang·Jong-Hyun Ahn·Hyunsoo Yang
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Abstract

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.

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Yang Wu, Xuezhong Ruan, Chih-Hsin Chen, Young Jun Shin, Youngbin Lee, Jing Niu, Jingbo Liu, Yuanfu Chen, Kun-Lin Yang, Xinhai Zhang, Jong-Hyun Ahn, Hyunsoo Yang. 2013-09-06. Graphene/liquid crystal based terahertz phase shifters. https://doi.org/10.1364/oe.21.021395

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