Fabrication and characterization of (rare-earth)-barium-copper-oxide (RE123 with RE=Y, Er, and Sm) films

Abstract

Epitaxial (rare-earth)Ba/sub 2/Cu/sub 3/O/sub 7/ films, RE123, with RE=Y, Er, and Sm have been fabricated using pulsed laser deposition on various single crystal substrates. Deposition of each material is optimized for T/sub c/. T/sub c/ values of 89.9 K, 91.0 K, and 93.0 K are obtained for Er123, Y123, and Sm123, respectively. T/sub c/ in RE123 films increases with increasing the ionic size of the rare-earth element as observed in bulk. Study of field- and angle-dependent J/sub c/ shows that the vortex pinning anisotropy is also affected by the rare-earth element. The Sm123 film has the best pinning characteristics in high magnetic fields among the investigated materials. The results will be discussed in relation to the crystal chemistry and internal stress due to the ionic size of rare-earth element.