Electrical assisted laser floating zone (EALFZ) growth of 2212-BSCCO superconducting fibres

摘要

The new electrical assisted laser floating zone {EALFZ) technique was used to grow superconducting fibres of Bi_2Sr_2CaCu_2O_8 (2212-BSCCO).The application of an electrical current through the crystallization interface proved to advantageously modify the phase nature and texture of 2212-BSCCO polycrystalline fibres compared to conventionally laser floating zone (LFZ) grown ones. The current application during the growth induces a selective and more intense ionic migration along the fibre axis. As a result, an increase in superconducting phase fraction and a decrease of residual melt were observed together with grain alignment intensification. The main outcome in the superconducting properties is the improvement of the critical current density at 77 K, from 1.2 x 10~3 A/cm~2, in the LFZ fibres, to 2.8 x 10~3 A/cm~2, in the EALFZ processed ones.