Nonmagnetic impurity effects in MgB${}_2$

Abstract

We study nonmagnetic impurity effects in MgB${}_2$ using the quasiclassical equations of superconductivity for a weak-coupling two-band model. Parameters in the model are fixed so as to reproduce experiments on MgB${}_2$ as closely as possible. The quasiparticle density of states and the specific heat are calculated for various values of the interband impurity scattering. The density of states changes gradually from a two-gap structure into the conventional single-gap structure as the interband scattering increases. It is found that the excitation threshold is not a monotonic function of the interband scattering. Calculated results for the specific heat are in good agreements with experiments on samples after irradiation.

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Cited by in corpus (3)

• Thermodynamics of Two - Band Superconductors: The Case of MgB${}_2$
• First-principles-based $\pm s$-wave modelling for iron-based superconductors:Studies for specific heat and nuclear magnetic relaxation rate
• Quasiclassical Theory for Thermodynamic Properties of the Two-Band Superconductor MgB${}_2$ under Magnetic Fields