Evidence for transformation from δTc to δl pinning in MgB2 by graphene oxide doping with improved low and high field Jc and pinning potential

Flux pinning mechanism of graphene oxide (GO) doped MgB2 has been systematically studied. In the framework of the collective pinning theory, a B-T phase diagram has been constructed. By adjusting the GO doping level, the pinning mechanism in MgB2 transformed from transition temperature fluctuation induced pinning, δTc pinning, to mean free path fluctuation induced pinning, δl pinning, is observed. Furthermore, in terms of the thermally activated flux flow model, the pinning potential in high field (B > 5 T) is enhanced by GO doping. The unique feature of GO is the significant improvement of both low field Jc and high field Jc. Disciplines Engineering | Physical Sciences and Mathematics Publication Details Xiang, F. X., Wang, X., Xu, X., De Silva, K. S.B., Wang, Y. & Dou, S. X. (2013). Evidence for transformation from δTc to δl pinning in MgB2 by graphene oxide doping with improved low and high field Jc and pinning potential. Applied Physics Letters, 102 (15), 152601-1-152601-5. Authors F X Xiang, X L Wang, X Xun, K S.B De Silva, Y X. Wang, and S X. Dou This journal article is available at Research Online: http://ro.uow.edu.au/aiimpapers/702 Evidence for transformation from δTc to δl pinning in MgB2 by graphene oxide doping with improved low and high field Jc and pinning potential F. X. Xiang, X. L. Wang, X. Xun, K. S. B. De Silva, Y. X. Wang et al. Citation: Appl. Phys. Lett. 102, 152601 (2013); doi: 10.1063/1.4799360 View online: http://dx.doi.org/10.1063/1.4799360 View Table of