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 µm 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 ∼7° from the tape plane. Very strong vortex pinning is evidenced by high critical current density J c values of ∼3.1 MA cm −2 at 77 K and ∼43 MA cm −2 at 4.2 K, and by a strongly enhanced irreversibility field H irr , which reaches that of Nb 3 Sn (∼28 T at 1.5 K) at 60 K, even in the inferior direction of axis. At 4.2 K, J c values are ∼15% of the depairing current density J d , much the highest of any superconductor suitable for magnet construction.