Determination of the relative influences of carbon doping and disorder on field and temperature dependent critical current density of MgB2

作者：Chen S K^*; Xu X; Kim J H; Dou S X; MacManus Driscoll J L

来源：Superconductor Science and Technology, 2009, 22(12): 125005.

DOI：10.1088/0953-2048/22/12/125005

SiC was mixed with Mg and B and reacted by either a one-step in situ or two-step method at 650 or 850 degrees C. By doing so, it was possible to determine the extent to which scattering via C doping influences the magnitude of field dependent critical current density, J(c)(H), compared to pinning via generation of microstructural disorder. The one-step reaction method leads toMg(2)Si formation and at the same time to more C doping of MgB2 than the two-step method. Carbon increases both the irreversibility field, H-irr, and upper critical field, H-c2 (T < 28 K). However, for the temperatures (6 and 20 K) and fields (up to 7 T) studied, pinning rather than scattering overwhelmingly dominates the magnitude of the field dependent critical current density.

• 出版日期2009-12