Effects of Sm-doping on Structures and Properties of YBCO Coated Conductors Fabricated by TFA-MOD Process

Abstract

The Sm-doping YBCO films, Y 1−x Sm x Ba 2 -Cu 3 O y and Y 1 Sm x Ba 2−x Cu 3 O y (x = 0.1, 0.3), were fabricated on LAO (00l) single-crystal substrates by TFA-MOD process in order to improve the superconducting properties of YBCO films. The XRD analyses indicated that these samples have a strong c-axis texture, but the secondary phase of BaCuO 2 are found from Y 1 Sm x Ba 2−x Cu 3 O y films with Sm 3+ substitution on Ba 2+ sites. High quality surface, better in-plane and out-of-plane texture of the Sm-doping films have been obtained compared with that of the undoped YBCO film. The Y 0.9 Sm 0.1 Ba 2 Cu 3 O y films showed the highest value of T c and J c in self-field. Superconducting properties of all Sm-doping films are better than those of the pure film. These results strongly suggest that Smsubstitution on Y or Ba sites of YBCO phase is a powerful method to efficiently improve J c and introduce artificial pinning centers in YBCO films.

Strong pinning at high growth rates in rare earth barium cuprate (REBCO) superconductor films grown with liquid-assisted processing (LAP) during pulsed laser deposition

“…Samples with a mixed rare-earth component have been shown to have mildly improved performance at 77 K [20][21][22][23]. However, it is at lower temperatures that such point defects are expected to be most beneficial, with previous studies predicting that they will become the major contribution to the vortex pinning force at low temperatures [24].…”

Enhancement by La-Al-O Doping in Y-Ba-Cu-O Films Both in Self-Field and Under Magnetic Field

“…An utmost important factor is the flux creep which can be refer to flux pining [4], [5]. Along the c-axis, there are poor natural pining centers, so introducing artificial pining centres (APCs), such as nano-scale impurities, columns and so on, become very popular [6], [7]. There are several ways to engineer these APCs, including rare-earth element doping [8], substrate modification [9], addition of nonsupercondctive particles [10]- [12] and so on.…”