Thermodynamic analysis of BaxK1 − xBiO3 using the Eliashberg theory

In order to understand the mechanism that gives rise to superconductivity in the ceramic superconductors of the type Ba_xK_{1 ? x}BiO₃, we analyze the thermodynamic properties with the use of the Eliashberg equations. For these calculations we used the electron-phonon spectral density function ²(ω)F(ω), calculated by Shirai et al. 1] from first principles for two different K concentrations, x=0.5 and x=0.7.