Structural and Physical Properties of High-Entropy REBa2Cu3O7-δ Oxide Superconductors.

In this study, we introduce the concept of high-entropy into high-temperature superconductors and report the successful synthesis of a series of high-entropy oxides, REBa₂Cu₃O_7-δ (REBCO), with superconducting critical temperature (T_c) around 92 K. The superconductivity transition temperatures of these compounds are very close to that of the parent superconductor, YBa₂Cu₃O_7-δ (YBCO). The temperatures of the zero-resistance appearing (T_c^zero), the critical current density (J_c) calculated from the hysteresis loop, and the irreversible fields (H_irr) of REBCO are not improved compared to that of YBCO. Our results indicate that the introduction of high-entropy elements with strong magnetic moments at RE site does not affect T_c, but may decrease other superconducting properties such as J_c, T_c^zero, and H_irr. [ABSTRACT FROM AUTHOR]