Bulk (Nd, Sm, Eu)1-xGdxBa2Cu3 Oy superconductors in which the Gd content x ranged from 0 to 0.25, were grown by the oxygen-controlled-melt-growth (OCMG) method. X-ray diffraction results show that the main phase is RE123 with a small amount of the second phase. SQUID measurements on the oxygenated samples showed that a small amount of Gd123 addition to (Nd, Sm, Eu)123 increased Tc and made the superconducting transition sharper. All the samples, except the Gd-free one, exhibited the secondary peak effect in the magnetization curves, which shows that the field-induced pinning is active, like the other RE123 fabricated by the OCMG process. The critical current density also increased with Gd addition, however, no systematic change was observed with the amount of Gd addition. A peak Jc value of 60,000 A/cm2 was recorded with an applied field of 1.2 T (H//c) at 77 K. The results suggest that, in the (Nd, Sm, Eu)123 system the addition of Gd is effective in achieving high Tc and a large Jc.
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