SUPERCONDUCTOR IMAGING SURFACE MAGNETOMETRY

The presence of superconducting surfaces in the vicinity of current so urces may be interpreted in terms of image theory. This concept has bo th experimental and theoretical practicality. Experimentally, sensing coils magnetic detection, when placed near such surfaces, perform in a gradiometric fashion. Iri order to explain this effect explicitly, a theoretical treatment of the magnetic fields in the presence of superc onducting surfaces and coils is presented. Expressions are derived for planar and spherical geometries that approximate practical experiment al situations. These expressions may be used to predict the expected g radiometric response of a coil as a function of the positions of the s ource and coil relative to the surface. (C) 1995 American Institute of Physics.