Tunable Dual-Band Ultrasensitive Stereo Metamaterial Terahertz Sensor

To overcome the effect of analyte thickness and limitation of single wavelength sensing, we propose an ultra-sensitive stereo metamaterial biosensor with double resonance frequencies based on coupling electric resonance and magnetic resonance. The electromagnetic analysis demonstrates that the double resonance coupling, induced by the stereo double-layer structure, can significantly improve sensitive biosensing at the terahertz frequency. The results show that by changing the size of the structure, each resonance frequency can be independently tuned in the range of 0.5–1.8 THz and the maximum refractive index sensitivity is 930.4 GHz/RIU. These results have significant implications for the detection of samples with different frequency points. The proposed ultra-sensitive stereo metamaterial structure has excellent potential for application in biomolecule detection and differentiation.