Trapping Mode Controlled Continuous Growth of SmBCO Bulk Superconductors

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.