Author : Gargee Sharma 1
Date of Publication :20th October 2016
Abstract: In the present study we investigated the theoretical calculation of Superconducting state parameter (SSP) by doping of MN on MgB2 superconductor for concentration (x=0.006, 0.007, 0.014, 0.016, 0.020). We use Ashcroft's pseudo potential in conjunction Random phase approximation (RPA) dielectric screening function with methodology based on BCS- Elias berg Mc. Millan framework in which material properties like electron-phonon coupling strength (λ) and Coulomb pseudo potential (μ*) are obtained from the knowledge of electron-ion pseudo potential. The super-conducting state properties like transition temperature (TC), isotope effect exponent (α) and interaction strength (N0V) are then obtained by using the values of λ, μ* and <ω2> relevant to the superconductor .It is also observed that addition of Manganese to superconductor MgB2 causes the parameters λ, μ*, α, N0V, TC decreases with increasing in Manganese concentration. Present calculation also observed that TC for alloys Mg1-xMnxB2 is excellent agreement with the experimental results. It is observed that the increase in doping concentration of MN causes all the superconducting parameters to decrease. This suggests decrease in superconducting behavior of MgB2 due to effect of magnetic impurity MN.
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