Universal disorder-induced transition in the resistivity behavior of strongly coupled metals

Abstract

At low temperatures (${\mathrm{T}}_{\mathrm{c}}$ ${\mathrm{theta}}_{\mathrm{D}}$) a new universal transition in the resistivity behavior of strongly coupled superconductors has been demonstrated experimentally: The power-law behavior changes from ${\mathrm{T}}^{\mathrm{n}}$ (n=3–5) to ${\mathrm{T}}^2$ as disorder increases, provided that the electron-phonon coupling λ is sufficiently high. The physics of the effect is probably based on the breakdown of the electron-phonon momentum-conservation law. Universal correlation allows independent estimates of λ.