Preparation of a high-T c superconducting magnetic flux transformer with a 100 mm bore coil and static magnetic field transfer at 77 K

Abstract

Herein, superconducting magnetic flux transformers with pickup coils of diameter 100 mm were prepared using a commercial RE123 high critical temperature (high-T c ) superconductive tape. A superconducting flux transformer requires a closed circuit containing a superconductive joint, which is difficult to prepare for a cuprate high-T c superconductor. Using the cut-and-wind method, seamless and large-bore coils were equipped to the flux transformer; these features are advantageous for non-destructive estimation and geological magnetic survey. The magnetic flux transfer of the applied static field caused by the spontaneously induced superconductive shield current at the liquid nitrogen temperature was confirmed, and the efficiency in the static field transfer, depending on the inductance of the coils in the flux transformer, was estimated.