Anisotropic magnetic-field dependence of the critical current density and microstructure for YBaCuO thin films

✍ Scribed by S. Kondoh; T. Matsubara; S. Ohashi; T. Morimoto

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 325 KB
• Volume: 185-189
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(91)91097-n

✦ Synopsis

Anisotropic magnetic-field dependence of the critical current density (Jc) of polycrystalline YBa2Cu307_6 thin films deposited on (lO0)MgO, (lO0)SrTiO 3 and a-axis oriented BaSnO 3 was studied.

For the films on MgO. Jc changes from Jc(B//substrate surface)~ IXlO 5 A/cm 2 to Jc(BJ. substrate surface)~4XlO 4 A/cm 2 at 77.3K and O.6T.

On the other hand, for the films on SrTiO 3, Jc is almost constant at about Jc(B//)= Jc(B_L)~ 3XlO 5 A/cm ~ under the same conditions.

Transmission electron microscopy shows that the films on MgO consist of c-axis oriented small YBa2Cu307_~ grains (~ 1 u m in size), while the films on SrTiO~ consist of a mixture of a-axis and c-axis oriented small YBa2Cu3OT_6grains (~O. Sum in size), These facts suggest that the dependence of Jc on the direction of the applied magnetic field strongly reflect the microstructure of the thin films.