Prevención de la obesidad en edad temprana

Abstract

In Al-free PrBa2Cu3O7-y single crystals the kink in the temperature dependence of magnetic susceptibility χab(T), connected with Pr antiferromagnetic (AFM) ordering, disappears after field cooling (FC) in a field Hab-plane. The kink in χc(T) remains unchanged after FC in Hc-axis. As a possible explanation, freezing of the Cu magnetic moments, lying in the ab-plane, caused by FC in Hab, hinders their reorientation and, due to coupling between the Pr and Cu(2) sublattices, ordering of the Pr3+ moments. A field-induced phase transition and a field dependence of the Pr3+ ordering temperature have been found for both Hc and Hab.