Theoretical and Experimental Research on Terahertz Metamaterial Sensor With Flexible Substrate

• Published in: IEEE photonics journal Vol. 14; no. 1; pp. 1 - 9
• Main Authors: Yao, Haizi, Mei, Hongying, Zhang, Weiwei, Zhong, Shuncong, Wang, Xiangfeng
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.02.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: biosensors; Electromagnetic fields; Fano resonance; Laser etching; Metamaterials; Refractive index; refractive index sensing; Refractivity; Resonant frequency; Sensitivity; Sensors; Substrates; Terahertz frequencies; Terahertz metamaterials; Thickness; thickness measurement
• ISSN: 1943-0655; 1943-0655; 1943-0647
• DOI: 10.1109/JPHOT.2021.3124414

A terahertz metamaterial refractive index/thickness sensor with flexible substrate, exhibiting low-frequency Fano resonance and high-frequency electromagnetically induced transparent (EIT) resonance, is proposed. The physical formation mechanisms of Fano and EIT resonances are investigated by calculating the electromagnetic field. Simulated results demonstrate that the refractive index sensing sensitivity based these two resonances are up to 60 and 100 GHz/RIU, and the thickness sensing sensitivity are up to 1 and 1.7 GHz/μm, respectively. Furthermore, the proposed sensor was fabricated using femtosecond laser etching technology, and its sensing performance was verified by the experimental results that it can distinguish different liquids and detect the polyimide film with different thicknesses less than 180 μm. The remarkable performances make the proposed metamaterial sensor has feasible capability for biological and chemical sensing in terahertz range.