Experimental and Numerical Study of Sensitivity Improvement in Near-Field Probes Using Single-Negative Media

In this paper, we present experimental verification of the sensitivity improvement of evanescent-field probes using single-negative (SNG) metamaterials. Artificial magnetic materials are designed and fabricated to realize a ??-negative SNG material. The response of an electrically small probe to an electrically small target is investigated numerically and experimentally. The deviation in the phase of reflection coefficient due to the target is measured. When an SNG layer is employed, phase shift due to the presence of a target is improved nine times compared to a probe without an SNG layer.