Boosting the Critical Current Densities With BaTiO 3 Doping in Single‐Domain GdBCO Bulks by TSMG Technique

ABSTRACT In this study, we employed commercial NdBCO single crystals as seeds and utilized the conventional top‐seeded melt growth (TSMG) method to fabricate GdBa 2 Cu 3 O 7‐δ (GdBCO) bulk samples, incorporating trace amounts (0.1 wt%) of micro‐ and nano‐sized BaTiO 3 (BTO) particles. The results demonstrated that single‐domain GdBCO bulk samples with highly oriented [00l] textures were prepared. Compared with the undoped samples, BTO doping could reduce the pore sizes within the bulks to some extent. Moreover, BTO‐doped samples exhibited better superconducting properties, including higher J c , and higher trapped field ( B tr ), and levitation force ( F L ). Particularly, the nano‐sized BTO‐doped sample exhibited the best superconducting performance and achieved a self‐field J c of 250 kA/cm 2 at 77 K, B tr of 0.403 T, and F L of 40.7 N. And this could probably be attributed to the formation of magnetic flux pinning centers from nano‐sized BTO and stacking fault defects.