Screening dependence of superconducting state parameters of Cu–Zr metallic glasses

Abstract

AbstractThe screening dependence of superconducting state parameters (λ, μ*, Tc, α and N0V) of nine metallic glasses of the Cu–Zr system has been studied in the BCS–Eliashberg–McMillan framework by employing five forms of dielectric screening function in conjunction with Ashcroft's potential. It is observed that the electron–phonon coupling strength (λ) and transition temperature (Tc) are quite sensitive to the form of the dielectric screening, whereas the Coulomb pseudopotential (μ*), isotope effect exponent (α) and effective interaction strength (N0V) show weak dependences on screening function. The RPA form of dielectric screening is observed to yield the best results for all the glasses of the Cu–Zr system studied in the present work. Present computations yield almost linear variation of Tc with concentration x of Cu in the Cu–Zr system, which is in agreement with the experimental data. A linear Tc equation is proposed by fitting the present results for RPA screening, which is in conformity with other results for the experimental data. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)