Electrically Tunable Reflective Terahertz Phase Shifter Based on Liquid Crystal
We present a reflective spatial phase shifter which operates at terahertz regime above 325 GHz. The controllable permittivity of the nematic liquid crystals was utilized to realize a tunable terahertz (THz) reflective phase shifter. The reflective characteristics of the terahertz electromagnetic waves and the liquid crystal parameters were calculated and analyzed. We provide the simulation results for the effect of the incident angle of the plane wave on the reflection. The experiment was carried out considering an array consisting of 30 × 30 patch elements, printed on a 20 × 20 mm quartz substrate with 1-mm thickness. The phase shifter provides a tunable phase range of 300° over the frequency range of 325 to 337.6 GHz. The maximum phase shift of 331° is achieved at 330 GHz. The proposed phase shifter is a potential candidate for THz applications, particularly for reconfigurable reflectarrays.
KeywordsLiquid crystals Phase shifter Reconfigurable antennas Terahertz devices
This work is supported by the National Natural Science Foundation of China (Grant No. 51607050), the Fundamental Research Funds for the Central Universities (Grant No. JD2017JGPY0006), and the Sichuan Science and Technology Support Project (No. 2016GZ0250).
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