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In this work, we report a novel approach for a continuous growth of SmBa2Cu3Oy (Sm123) bulk superconductors. Under a conventional slow-cooling mode, it was found that the crystal growth slows down and terminates ahead of time due to a reduced effective supersaturation (σeff). Apart from commonly supposed two effects, RE2BaCuO5 (RE211, RE = rare earth element) coarsening in the melt and RE211 segregation at the growth front, we find that the noticeable reduction of t.c.s. (temperature coefficient of solubility) plays a significant role in the σeff declining phenomenon in the Sm–Ba–Cu–O system. In our new process, an accelerated cooling was applied to maintain a sufficient σeff so that a trapping mode controlled continuous growth is realized.

In this work, we report a strengthened superheating effect caused by a buffering YBa2Cu3O y (YBCO or Y123) layer in the Nd1+x Ba2−x Cu3O7−y (NdBCO or Nd123) thin film with MgO substrate (i.e., NdBCO/YBCO/MgO thin film). In the cold-seeding melt-textured (MT) growth, the NdBCO/YBCO/MgO film presented an even higher superheating level, about 20 °C higher than that of nonbuffered NdBCO film (i.e., NdBCO/MgO film). Pole figure (X-ray Φ-scan) measurement reveals that the NdBCO/YBCO/MgO film has better in-plane alignment than the NdBCO/MgO film, which may be the main origin of the enhanced thermal stability. Using this NdBCO/YBCO/MgO film as the seed and under a maximum processing temperature (T max) up to 1120 °C, we succeeded in growing various RE1+x Ba2−x Cu3O7−y (REBCO, RE=Gd, Sm, Nd, RE refers to rare elements) bulk superconductors and recycling the failed REBCO (RE=Y) bulks in a simple and feasible process.

In this work, we reported that a large size SmBCO, 32 mm in diameter, was successfully grown in air by the cold-seeding method. During the preparation, a Ba-rich Sm 2 Ba 4 Cu 2 O y (Sm242) was employed to refine T c , while a nano-sized Sm 2 Ba 4 CuBiO z (Sm2411) phase was introduced to reinforce J c . In addition, an NdBCO thin film seed was used to guarantee that a high maximum processing temperature ( T max ) could be adopted for the growth of large sized bulk.

In this work, we report a strengthened superheating effect caused by a buffering YBa2Cu3Oy (Y123 or YBCO) layer in the Nd1+xBa2-xCu3O7-y (Nd123 or NdBCO) thin film with MgO substrate (i.e., NdBCO/YBCO/MgO thin film). In the cold-seeding melt-textured (MT) growth, the NdBCO/YBCO/MgO film presented an even higher superheating level, about 20 {\deg}C higher than that of non-buffered NdBCO film (i.e., NdBCO/MgO film). Using this NdBCO/YBCO/MgO film as seeds and undergoing a maximum processing temperature (Tmax) up to 1120 {\deg}C, we succeeded in growing various RE1+xBa2-xCu3O7-y (REBCO, RE=rare elements) bulk superconductors, including Gd1+xBa2-xCu3O7-y (GdBCO), Sm1+xBa2-xCu3O7-y (SmBCO) and NdBCO that have high peritectic temperatures (Tp). The pole figure (X-Ray \phi-scan) measurement reveals that the NdBCO/YBCO/MgO film has better in-plane alignment than the NdBCO/MgO film, indicating that the induced intermediate layer improves the crystallinity of the NdBCO film, which could be the main origin of the enhanced thermal stability. In short, possessing higher thermal stability and enduring a higher Tmax in the MT process, the NdBCO/YBCO/MgO film is beneficial to the growth of bulk superconductors in two aspects: (1) broad application for high-Tp REBCO materials; (2) effective suppression against heterogeneous nucleation, which is of great assistance in growing large and high-performance REBCO crystals., Comment: 9 pages, 4 figures