A new apparatus for measuring the critical currents of hard type-II superconductive wires and tapes in high fields as a function of temperature throughout their superconducting phase

The paper describes an update of an earlier apparatus which measures the critical current of superconducting wires and tapes as a function of magnetic field and temperature. The critical element is a compact probe of 25 mm diameter which can be inserted into the bore of one of several high-field magnets. A description is given of the design and critical features of the probe which incorporates high-resolution thermometry and accurate temperature control in the demanding environment of high sample currents and large magnetic fields. Data obtained on a sample of multifilamentary V3Ga wire are presented as an illustration of the probe's capabilities. (author)