Abstract
Temperature dependence behavior of resistivity for nano diamond doped MgB
2 superconductor was measured in different magnetic field 0
T
⩽
H
⩽
8
T. Irreversibility (
H
irr) is enhanced by nano diamond doping. We reveal that flux-creep activation energy is a nonlinear function of current density
U
0
∝
J
c
-
0.2
. In order to determine the activation energy of thermally activated flux flow, Arrhenius law has been taken into account. The magnetic field dependence of flux flow activation energy of nano diamond doped MgB
2 superconductors was calculated from the slope of the linear part of the Arrhenius plot and found to be decrease corresponding with applied field. Therefore, the critical current density of this sample will need to be enhanced for practical applications.