In this study, we have fabricated high-entropy type RE123 superconducting thin films that RE site is replaced multiple Gd, Sm, Y, Nd, Eu elements, by fluorine-free metal organic deposition (FF-MOD) method and evaluated their superconducting properties. There are few reports of fabricating high-entropy type RE123 superconducting thin films by FF-MOD. Typically, alloys containing more than five elements with the ratio between 5 to 35 at% are known as high-entropy alloys, and their crystal robustness is very strong. Therefore, it is expected that high-entropy type RE123 superconductors can be introduced artificial pinning centers more than RE123 having one kind of RE without deterioration of crystallinity. Fist fabricated Gd_0.44Sm_0.56Ba₂Cu₃O_7-δ showed critical current densities of 1.18 MA/cm² at 0 T and 0.05 MA/cm² at 1 T. We have optimized the fabrication process and studied the superconducting properties of high-entropy type RE123 thin films.

Keywords: high-entropy, metal organic deposition, REBCO, FF-MOD