Sensitivity detection of imidacloprid pesticide using a metasurface sensor in THz spectrum regime

Abstract

Imidacloprid (C9H10ClN5O2) pesticide is frequently used in agriculture as it effectively controls various insect pests. Accurate detection of imidacloprid concentrations is crucial for food safety and other fields. This work proposes a novel metasurface (MS) sensor with efficient sensitivity in the THz frequency regime to detect imidacloprid pesticides. The MS sensor has an electrical size of 7.17λ × 7.17λ with the smallest wavelength. The transmission coefficient remains stable for the metasurface sensor’s TE and TM polarization modes. Due to the symmetrical design, it exhibits strong electric and magnetic field enhancement with polarization insensitivity for different incident angles. The sensing capability is tested by implementing different sample analyte thicknesses of imidacloprid in the top surface of the MS sensor. Imidacloprid analyte thickness increases cause a red and blue change in the metasurface’s transmission frequency. The simulation results show that the suggested MS sensor has a refractive index (RI) sensitivity of 0.125 THz/RIU, and a Q factor of 5.262 and 4.084. This is a simple, cost-effective, sufficiently sensitive, and efficient THz MS sensor with a wide range of applications in pesticide concentration measurement, including imidacloprid.

Keywords

• THz Technology
• Pesticide
• Imidacloprid
• Sensor
• Sensitivity
• Q factor