Electronic Integration Technique for Measuring Magnetization of Hysteretic Superconducting Materials

Abstract

A simple system capable of continuously recording complete magnetization curves for hysteretic superconductors is described. It allows the applied field to be cycled slowly in order to avoid transient effects in the specimen material. A voltage proportional to the differential susceptibility of the material is integrated by a chopper stabilized solid state amplifier, and plotted on an X-Y recorder as a function of applied field. The system is capable of recording magnetization curves over periods of 15 min with an over-all uncertainty of 5% or less.