Coexistence of the δl and δTc flux pinning mechanisms in nano-Si-doped MgB2

Authors

Shaban R. Ghorbani, University of WollongongFollow
Xiaolin Wang, University of WollongongFollow
Md S. Hossain, University of WollongongFollow
S X. Dou, University of WollongongFollow
Sung-Ik Lee, Sogang University, South Korea

RIS ID

31902

Publication Details

Ghorbani, SR, Wang, P, Hossain, M, Dou, SX & Lee, S (2010), Coexistence of the δl and δT_c flux pinning mechanisms in nano-Si-doped MgB_2, Superconductor Science and Technology, 23(2), pp. 1-4.

Abstract

The flux pinning mechanisms of nano-Si-doped MgB₂ are reported in this work. The field dependence of the critical current density, J_c(B), was analyzed within the collective pinning model. We found that the mechanisms for both δl pinning, i.e., pinning associated with charge-carrier mean free path fluctuations, and δTc pinning, which is associated with spatial fluctuations of the transition temperature, coexist in the nano-Si-doped MgB₂ samples, while H_c2 increases greatly with increasing nano-Si doping level. However, their contributions are strongly temperature dependent. The δl pinning is dominant at low temperatures, decreases with increasing temperature, and is suppressed completely at temperatures close to the critical temperature, T_c. However, the δT_c pinning mechanism shows opposite trends.

Grant Number

ARC/DP0770205, ARC/LX0882225

Additional Grant Number

http://purl.org/au-research/grants/ARC/DP0770205, http://purl.org/au-research/grants/ARC/LX0882225