High Sensitivity Electrical Properties Measurement of Graphene-based Composites using Interferometric Near-field Microwave Technique
Abstract High sensitivity electrical properties measurement of composite materials using an interferometric near-field microwave technique is proposed in this paper. A one-port calibration model is developed to relate the measured transmission coefficient to the local properties of the material. To represent the probe-composite sample interaction, an electrical model based on lumped elements is developed. As a demonstration, complex permittivity and conductivity of composite materials prepared with polyvinyl chloride (PVC) and different concentration of graphene are experimentally determined at 2.45 GHz. The obtained results show that the proposed technique is sensitive for the detection of small contrast of permittivity and conductivity in composite material. When graphene concentration increases from 1 to 30%, the conductivity increases from 0.0061 s/m to 0.056 s/m.