Role of anisotropic impurity scattering in anisotropic superconductors
Physical Review B (Condensed Matter)
A theory of nonmagnetic impurities in an anisotropic superconductor including the effect of anisotropic (momentum-dependent) impurity scattering is given. It is shown that for a strongly anisotropic scattering the reduction of the pair-breaking effect of the impurities is large. For a significant overlap between the anisotropy functions of the scattering potential and that of the pair potential and for a large amount of anisotropic scattering rate in impurity potential the superconductivity
... mes robust vis a vis impurity concentration. The implications of our result for YBCO high-temperature superconductor are discussed.