Author(s): Ju, XC (Ju, Xiacao); Wang, WG (Wang, Weiguang); Liu, BC (Liu, Bingchao); Hou, YZ (Hou, Yanzhao); Wen, HS (Wen, Huashun); Yang, DQ (Yang, Daquan)

Source: OPTICA APPLICATA Volume: 52 Issue: 4 Pages: 551-563 DOI: 10.37190/oa220406 Published: 2022

Abstract: Terahertz (THz) linear-to-circular (LTC) polarization conversion plays a crucial role in imaging and 6G wireless communication. This paper will give an account of a thermally tunable THz LTC polarization converter by using the active all-dielectric metasurface. It consists of zirconium oxide (ZrO2) microsphere resonators, active strontium titanate (STO) cladding, and flexible polyimide substrate. Through numerical simulation, the amplitude of the ellipticity of the proposed polariza-tion converter at 0.265 THz is -1, indicating that perfect right-hand circular polarization (RHCP) wave is achieved. Meanwhile, the amplitude of the ellipticity is less than -0.8 between 0.247 and 0.278 THz (relative bandwidth is 12%). In addition, with the temperature changes of 180 K (from 200 to 380 K), the operating frequency of the converter can be tuned from 0.220 to 0.291 THz, a sensitivity about 39 GHz/100 K is achieved. Besides, the modulation depth of the ellipticity am-plitude can achieve 92% at 0.220 THz, which demonstrates that the converter can output terahertz wave with different polarization states, and the device can be fabricated on a large scale. These perfect conversion performances show that the converter has potential applications in high-speed communication and imaging.

Accession Number: WOS:000913169500006

ISSN: 0078-5466

eISSN: 1899-7015

Full Text: https://opticaapplicata.pwr.edu.pl/files/pdf/2022/no4/optappl_5204p551.pdf