Disorder and superfluid density in overdoped cuprate superconductors

Abstract

One of the hallmarks of clean, $d$-wave superconductivity is a linear temperature dependence of superfluid density in the low-temperature limit. Here, the authors show that weak scattering, combined with a realistic model of the cuprate Fermi surface, allows the linear behavior of superfluid density to persist in the presence of disorder even in the regime where the superfluid density and the transition temperature are strongly suppressed from their clean-limit values. This leads to a superfluid density that is both correlated with the transition temperature and linear in temperature, consistent with recent experiments on overdoped La${}_{2-x}$Sr${}_{x}$CuO${}_{4}$.