High Cooling Rate for LRE123 Stoichiometry Control in Preparation of High‐ T _c Bulk Superconductors

After decades of development, high‐temperature superconductors are undergoing an important stage from laboratory research to practical applications. Among all candidates, LRE _{1+ x} Ba _{2− x} Cu ₃ O _{7− δ} (LRE123, LRE for light rare‐earth elements) oxides possess outstanding critical transition temperatures and high critical current densities. However, like many functional materials, LRE123 superconductors greatly suffer from cation off‐stoichiometry resulting from the LRE ³⁺ /Ba ²⁺ substitution, which adversely affects their performance. Recently, it is found that the cooling rate, as a decisive factor of crystallization, also serves as a powerful tool for regulating the oxygen vacancy and further managing cation stoichiometry. This paper provides an overview of the newly reported cooling‐rate‐control melt‐growth of LRE123 bulks with high superconducting performance. The underlying mechanism correlated with superconducting properties is comprehensively elucidated.