METHOD AND INSTRUMENT FOR MEASURING CRITICAL CURRENT DENSITY AND CURRENT-VOLTAGE CHARACTERISTIC OF SUPERCONDUCTOR THICK FILM

摘要

PROBLEM TO BE SOLVED: To provide a measuring method and instrument for nondestructively and noncontactingly measuring exactly a critical current density and a current-voltage characteristic of a superconductor thick film. SOLUTION: An alternating current is made to flow in a coil arranged just above the superconductor thick film, the critical current density of the superconductor thick film is found based on an alternating current value corresponding to a point where an increase of the third harmonic induced voltage gets moderate abruptly by detecting the current and the third harmonic induced voltage induced in the coil by the current. The current-voltage characteristic of the superconductor thick film is measured by changing frequency of the alternating current to measure the critical current densities a plurality of times, using the method. COPYRIGHT: (C)2005,JPO&NCIPI