Vanacken, J., S. Libbrecht, M. Maenhoudt, C. Van Haesendonck, E. Osquiguil, and Y. Bruynseraede. "The magnetic moment relaxation in oxygen-deficient YBa2Cu3Ox." Physica C: Superconductivity and its applications 197, no. 1-2 (1992): 9–14.
Abstract: The magnetic moment relaxation in polycrystalline YBa2Cu3Oxmaterial has been studied using zero-field-cooled measurements. The temperature dependence of the relaxation rate shows a field-dependent maximum. When the oxygen content is reduced, the maximum shifts towards lower temperatures. This shift is directly related to a decrease of the intragrain critical current density in the oxygen-deficient material, inducing a decrease of the field H* for complete flux penetration. The characteristic activation energies for depinning in the oxygen-deficient material are below 20 meV.
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