Application of bi-functional polarization-converting meta-material for microwave solution concentration detection

• Published in: Optical materials Vol. 150; p. 114836
• Main Authors: Chen, Linyue, Gao, Yulong, Zhao, Ling, Jing, Huihui, Kang, Jinfeng, Li, Wei, Wang, Jiayun, Qu, Zeng, Zhang, Binzhen, Duan, Junping
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2024
• Subjects: Meta-material; Microwave; Polarization conversion; Solution detection; Microwave; Meta-material; Polarization conversion; Solution detection
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2024.114836

A bi-functional meta-material structure capable of broadband linear polarization (LP) conversion and microwave bio-rapid detection has been designed. The designed structure consists of a double slit-split ring with a cross-shaped crossed metal strip structure. The surface layer consists of metallic copper uniformly sputtered on the dielectric layer F–4B, and the incident wave resonates with the meta-material structure with electromagnetic coupling, which achieves a broadband linear polarization conversion function of 7 GHz within the high-frequency band of 10.9 GHz–17.9 GHz, with a relative bandwidth of about 48.6 %. The polarization conversion wave peak at 6.39 GHz in the low frequency band can be used to realize the microwave biological rapid detection function, which can be used to classify and identify ethanol (alcohol), glucose solution, sodium chloride solution, and so on, and detect the concentration. When the refractive index of the sample gradually changed from 1.0 to 2.0 the polarization conversion peak showed a significant red shift, and the peak polarization conversion rate always remained above 99 %. On the experimental side, we processed and fabricated a sample of the meta-material structure, and conducted practical tests on the polarization effect and solution concentration detection application, and the test results were satisfactory. The designed meta-material structure has a wide range of applications in the field of microwave biological rapid detection and millimeter-wave radar systems. •Bifunctional structure•Broadband linear polarization•Polarization solution concentration detection.