Principles of superconductor imaging surface gradiometry

Abstract

Magnetic sources in the vicinity of superconducting surfaces produce images in such a way that a single pick-up coil parallel to the surface acts as a first order gradiometer. The principles will be described, together with specific discussions of the imaging by planar and spherical surfaces. The fact that these surfaces also deflect noise due to remote sources make this concept particularly appealing as a method for detecting extremely weak sources in a hostile environment. Possible applications to neuromagnetometry, corrosion detection and non-destructive evaluation will be discussed. 2 refs., 2 figs