Magnetization of superconducting lanthanum copper oxides

Abstract
Magnetization studies of the high-transition-temperature lanthanum-copper-oxide superconductors have been carried out to determine the electromagnetic and flux-pinning properties of these materials. Over much of the field-temperature plane the magnetization curves are highly reversible, which allows thermodynamic realtions to be used to obtain an estimate of the free energy. The material appears to have a granular character and very low flux pinning.