A Comprehensive Evaluation Method for Sensing Characteristics of Multi-Peak Terahertz Metamaterials Sensor in Polarization Mode

Abstract

Abstract In this study, the multi-peak terahertz metamaterials sensors are designed and fabricated, whose structures are the asymmetrical single split ring (SSR) and three split rings (TSR). The resonant formation and sensing mechanism of the two structures are investigated by using the finite-difference time-domain (FDTD) method. Vitamin B6 (VB6) and its reactants with bovine serum protein (BSA) are tested as the medium, and the sensing experiments of the SSR and TSR are carried out. The experimental and simulation results indicate the consistent law, which is the sensitivity of the resonance in the transverse magnetic (TM) mode is much greater than that in the transverse electric (TE) mode. According to the weighted average method and the law for unequal precision measuring, the quality factor of the resonance is used as the weighting coefficient to calculate the comprehensive evaluation parameter (CEP) of the multi-peak metamaterials sensors in the TE and TM modes based on the experimental data. When the CEP and frequency shifts are as the evaluation parameter in experiments, the law’s variation of the CEP is consistent with that of the frequency shift, indicating that it is feasible to characterize the sensing characteristics of metamaterials with the CEP, which presents simplified characteristics of multi-peak metamaterials at different polarization modes. The method implies that the different influencing factors may be integrated into the CEP with the idea of weight, which promotes the practical application of the metamaterials sensor. The revelation of the sensing law also provides a method for the design of the terahertz metamaterials sensor with the high sensitivity.

Keywords

• Terahertz MMs sensor
• multi-resonance mode
• polarization mode
• weighted frequency shift