A high critical current density MOCVD coated conductor with strong vortex pinning centers suitable for very high field use

We have made extensive low temperature and high field evaluations of a recent 2.1 mu m thick coated conductor (CC) grown by metal-organic chemical vapor deposition (MOCVD) with a view to its use for high field magnet applications, for which its very strong Hastelloy substrate makes it very suitable. This conductor contains dense three-dimensional (Y, Sm)(2)O-3 nanoprecipitates, which are self-aligned in planes tilted similar to 7 degrees from the tape plane. Very strong vortex pinning is evidenced by high critical current density J(c) values of similar to 3.1 MA cm(-2) at 77 K and similar to 43 MA cm(-2) at 4.2 K, and by a strongly enhanced irreversibility field H-irr, which reaches that of Nb3Sn (similar to 28 T at 1.5 K) at 60 K, even in the inferior direction of H parallel to c axis. At 4.2 K, J(c) values are similar to 15% of the depairing current density J(d), much the highest of any superconductor suitable for magnet construction.