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We report the synthesis and variation of superconductivity parameters such as transition temperature Tc, upper critical field Hc, critical current density Jc, irreversibility field Hirr and flux pinning parameter (Fp) for the MgB2-xCx system with nano-Carbon doping up to x=0.20. Carbon substitutes successfully on boron site and results in significant enhancement of Hirr and Jc(H). Resistivity measurements reveal a continuous decrease in Tc under zero applied field, while the same improves remarkably at higher fields with an increase in nano-C content for MgB2-xCx system. The irreversibility field value (Hirr) is 7.6 & 6.6 Tesla at 5 and 10K respectively for the pristine sample, which is enhanced to 13.4 and 11.0 Tesla for x = .08 sample at same temperatures. Compared to undoped sample, critical current density (Jc) for the x=0.08 nano-Carbon doped sample is increased by a factor of 24 at 10K at 6 Tesla field.
Polycrystalline MgB2-xCx samples with x=0.05, 0.1, 0.2, 0.3, 0.4 nano-particle carbon powder were prepared using an in-situ reaction method under well controlled conditions to limit the extent of C substitution. The phases, lattice parameters, micros
The high field magnetization and magneto transport measurements are carried out to determine the critical superconducting parameters of MgB2-xCx system. The synthesized samples are pure phase and the lattice parameters evaluation is carried out using
Polycrystalline MgB2-nDx (x= 0 to 0.1) samples are synthesized by solid-state route with ingredients of Mg, B and n-Diamond. The results from magneto-transport and magnetization of nano-diamond doped MgB2-nDx are reported. Superconducting transition
Low resistivity (clean) MgB2 bulk samples annealed in Mg vapor show an increase in upper critical field Hc2(T) and irreversibility field Hirr(T) by a factor of 2 in both transport and magnetic measurements. The best sample displayed Hirr above 14 T a
The synthesis and characterization of PVA (Poly Vinyl Acetate) doped bulk MgB2 superconductor is reported here. PVA is used as a Carbon source. PVA doping effects made two distinguishable contributions: first enhancement of Jc field performance and s