کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1820241 | 1525768 | 2008 | 4 صفحه PDF | دانلود رایگان |

Ba2CaCu2O4(O2−yFy) (F-0212), a new high-Tc superconductor (HTSC) including fluorine at an apical site, is an attractive material for application because it shows a highest Tc of 108 K and has thin spacing between conduction layers that is favorable for high critical current density (Jc) and irreversibility field (Birr). The polycrystalline samples of F-0212 were synthesized under high pressure. A doping state was controlled from under doping (Tc = 82 K) to slightly-over doping (Tc = 106 K) via optimally-doping (Tc = 108 K). From the DC magnetization hysteresis loops, we determined the intragrain Jc and Birr using Bean’s critical state model. The Jc and Birr properties of F-0212 were found to improve rapidly as the doping state changes from under doping to slightly-over doping to via optimally doping state. The irreversibility lines for the optimally- and slightly-over doped F-0212 are higher than optimally-doped Bi-2212. However, they are much lower than that of Cu-1212 (Y-123) though the spacing of F-0212 is thinner than that of Cu-1212. This indicates that property of the spacing is important to enhance Birr as well as its thickness. An anisotropy factor for under doped F-0212 was estimated to 118 from a 3D–2D crossover field of about 0.28 T.
Journal: Physica C: Superconductivity and its Applications - Volume 468, Issues 7–10, 1 April 2008, Pages 773–776