Highly Sensitive Terahertz Metamaterial Sensor with Enhanced Spatial Distribution of Strong Electric Field

Abstract

The sensitivity of terahertz refractive index sensors depends critically on the amplitude and spatial distribution of electric field where the analyte locates. A sensitive THz sensor was proposed based on metamaterials composed of two asymmetrically arranged C-shaped metallic structures. The resonance frequency is 758.6 GHz and the refractive index sensitivity is 128.2 GHz/RIU when the analyte thickness is 2 $\mu$m. Simulation results demonstrate that the proposed sensor is more sensitive than the traditional aDSRR structure. It serves as a new optimization method for the design of high-sensitivity metallic metamaterials, and has potential applications in trace materials detection and biosensing.