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On the rate of Tc suppression by the interband impurity scattering in MgB2

B. Mitrovic
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Abstract

We calculate the change in the superconducting transition temperature Tc of MgB2 caused by interband nonmagnetic impurity scattering using the Eliashberg theory for the two-band model of this compound. Much slower rate of Tc suppression is obtained compared to the prediction based on the BCS treatment of the two-band model which ignores renormalization and damping associated with the electron-phonon interaction. Hence, the interband impurity scattering rates deduced from experiments on MgB2 using the formula which results from the BCS approach to the two-band model are underestimated. We generalize the BCS treatment of the two-band model to include renormalization effects of the electron-phonon interaction and find an excellent agreement with the full strong coupling calculation.

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B. Mitrovic. 2004-12-02. On the rate of Tc suppression by the interband impurity scattering in MgB2. https://doi.org/10.1088/0953-8984%2F16%2F49%2F016

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