Study of fluctuation induced conductivity on nano diamond doped bulk MgB2 superconductor

Carbon doped materials play a vital role in modern solid-state electronics. Carbon can crystallise in the form of diamond and graphite due to the very versatile nature. The fluctuation effect of nano diamond (ND) on bulk MgB 2 system has been studied. The resistive transition broadening of all the employed samples decreases as the magnetic field increases. The result shows the temperature derivative of resistivity, d?/dT under the different magnetic field 0T ≤ H ≤ 8T of bulk ND-doped MgB2 system. The fluctuation induced conductivity (FIC) for different ND doped MgB2 samples are discussed under different magnetic fields 0T ≤ H ≤ 8T. The coherence length, ξc(0) for all possible cases in zero fields have been estimated and plotted. In this paper, we report the study of FIC of ND doped bulk MgB2 system in presence of magnetic field 0T ≤ H ≤ 8T. Result shows the decrease of transition temperature as we increase the magnetic field in all doped samples. The temperature derivative of resistivity, d?/dT is also discussed in different magnetic field and different doping concentration. The results show variation of FIC in δσ vs Ε-1 plot in different ND doped MgB2 samples under the range of 0T ≤ H ≤ 8T. The calculated coherence length, ξc(0), slightly decreases when we increase the doping concentration for ND doped MgB2 system at zero field. Copyright © 2009 Inderscience Enterprises Ltd.