Pinning enhancement and critical current densities in (Sm/sub 0.5/Y/sub 0.5/)Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// superconductor

摘要

A fabrication method of homogeneous (Sm/sub 0.5/Y/sub 0.5/)Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// superconductor substituting Y with Sm has been developed using a zone melting process. A sample prepared by this method showed well textured microstructure and (Sm/sub 0.5/Y/sub 0.5/)/sub 2/BaCuO/sub 5/ particles were uniformly dispersed in large (Sm/sub 0.5/Y/sub 0.5/)Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// grain. The sample showed a sharp superconducting transition at 90.3 K. The magnetization measurements of the (Sm/sub 0.5/Y/sub 0.5/)Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// sample exhibited enhanced flux pinning compared with YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// samples without Sm. Critical current densities of (Sm/sub 0.5/Y/sub 0.5/)Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// were 1.8/spl times/10/sup 4/ A/cm/sup 2/ at 10 kOe and 77 K.