Investigation of the effect of Al plasma treatment on the superconducting properties of YBa2Cu3O7−δ

Abstract

The effect of the partial substitution of Cu for Al on the structural, compositional, and magnetic properties of polycrystalline compounds YBa2Cu3O7−δ was studied. All prepared samples turned out to be single-phase with a small fraction of Ba secondary phases. Substitution of more than 2% aluminum causes an increase in spurious phases. DC susceptibility measurements show that the superconducting transition temperature TC decreases. Hysteresis loops show that magnetic irreversibility decreases with increasing Al content. The critical current density JC obtained using the Bean formula does not follow the same change. Al compensates for a decrease in JС and an increase in its content near the solubility limit gives a higher JС than in an undissolved sample.