Laser zone-melted Bi-Sr-Ca-Cu-O thick films

Directionally solidified superconducting Bi-Sr-Ca-Cu-O thick films have been fabricated by laser zone melting. Highly aligned grain structures were obtained. Films with no post-processing anneal showed Tc(R=0)=82 K and transport critical current densities Jc as high as 450 A/cm2 at 77 K and 5400 A/cm2 at 60 K. After annealing for 65 h at 850 °C, Tc increased to 85 K, and the best sample showed Jc =2200 A/cm2 at 77 K and 11 200 A/cm2 at 60 K.