Phonon-limited resistivity of high-Tcoxides: A strong-coupling calculation

The equations of the lowest-order conserving Green’s-function approximation for the phonon-limited resistivity are solved numerically. The input functions ${\mathrm{\alpha }}^2$F(ω) and ${\mathrm{\alpha }}_{\mathit{t}\mathit{r}}^2$F(ω) are calculated from a screened ionic model for ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_7$ and lead to integrated coupling constants λ∼3 and ${\lambda }_{\mathit{t}\mathit{r}}$∼1. The calculated temperature dependence of the resistivity and the width of the Drude peak as well as the absolute values of the prefactors are in excellent agreement with experiment. This result shows, in particular, that the observed resistivity in high-${\mathit{T}}_{\mathit{c}}$ oxides does not imply a weak electron-phonon coupling.