Specific-heat discontinuity in impure two-band superconductors Academic Article uri icon


  • The Ginzburg-Landau coefficients and the jump of the specific heat are calculated for a disordered two-band superconductor. We start with the analysis of a more general case with arbitrary anisotropy. While the specific-heat discontinuity at the critical temperature Tc decreases with increasing disorder, its ratio to the normal-state specific heat at Tc increases and slowly converges to the isotropic value. For strong disorder the deviation from the isotropic value is proportional to the elastic electron-scattering time. In the case of a two-band superconductor we apply a simplified model of the interaction independent of the momentum within a band. In the framework of this model all thermodynamic variables can be found explicitly at any value of the scattering rate. This solution explains the sample dependence of the specific-heat discontinuity in MgB2 and the influence of disorder on the critical temperature. 2003 The American Physical Society.

published proceedings

  • Physical Review B

author list (cited authors)

  • Mishonov, T. M., Penev, E. S., Indekeu, J. O., & Pokrovsky, V. L.

citation count

  • 14

publication date

  • September 2003