Critical current density dependence on orientation of Bi-free needle-like crystals in Bi2Sr2Ca1Cu2O8 thick films

✍ Scribed by S. Patel

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 347 KB
• Volume: 34
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(94)90177-5

✦ Synopsis

The growth of superconducting Bi2Sr2CalCu208 thick films is generally accompanied by the distribution of Bi-free needle-like crystals. The sizes of these crystals reported in the literature vary significantly and it seems that the smaller the crystals, the higher the critical current density is. The effect of the orientation and size of these crystals on the critical current density is theoretically investigated. Results show that the superconducting to normal transition in the film is initiated in regions where the crystals have the greatest converging constrictions. Also, the size, orientation and concentration can have a profound detrimental effect on the transport current properties of these films. Alignment of the crystals in the direction of current flow can reduce the degradation in the transport properties.