Measuring apparatus for calorimetric determination of the AC losses of superconductors

摘要

The invention relates to a measuring apparatus for determining the AC losses of superconductors in AC magnetic fields of arbitrary frequency. The measuring apparatus consists of a cylindrically shaped sample holder on which the superconductor to be measured is wound. During the measurement, the sample is surrounded by a medium, having low thermal conductivity, which serves as a thermal resistance with respect to the surrounding liquid helium bath. The applied AC field leads to an increase in the temperature of the sample, which increase is a measure of the losses. Using a heating device, the same heating as with the application of the AC magnetic field can be produced, by means of which the AC losses of the superconductor can be ascertained. The series measurement of samples can therefore be carried out with low time expenditure.