Near-field probes using metamaterial inclusions for enhanced sensitivity

Near-field probes are attractive because they provide sub-wavelength resolution. Typical detection using near field probes involves defects or irregularities present on the surface of the material. Sub-surface defects or irregularities are much more difficult to detect due to the fast decay of evanescent waves emanating from the probe. This work present novel probes employing metamaterial particles which work to substantially enhance the evanescent field energy in the vicinity of the probe, thereby increasing the sensitivity of the probe and enabling subsurface detection. Two experiments are presented where conducting metallic objects immersed in saline water and sand are detected. The results and findings presented here are expected to have strong implications in a wide range of sub surface detection challenges including detection of biological anomalies in human tissue, land mine detection, through-wall detection amongst other applications.