Specific heat of MgB2 in a one- and a two-band model from first-principles calculations
نویسنده
چکیده
The heat capacity anomaly at the transition to superconductivity of the layered superconductor MgB2 is compared to first-principles calculations with the Coulomb repulsion, μ∗, as the only parameter which is fixed to give the measured Tc. We solve the Eliashberg equations for both an isotropic one-band and a two-band model with different superconducting gaps on the π-band and σ-band Fermi surfaces. The agreement with experiments is considerably better for the two-band model than for the one-band model. Submitted to: J. Phys.: Condens. Matter PACS numbers: 74.25B, 74.80Dm, 74.72.-h Specific heat of MgB2 from first-principles calculations 2
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