Evidence for Matthiessen's rule in the normal state resistivity of zinc doped yttrium barium copper oxide

Abstract

The authors have measured the electrical resistivity rho (T) for a number of sintered samples of Y₁Ba₂(Cu_1-xZn_x)₃O₇ with x in the range 0.01-0.10. Above T_c, d rho /dT falls smoothly with increasing bulk density and is independent of x as confirmed by measurements on alloys of equal density. Taking d rho /dT to be independent of x, they find that the extrapolated residual resistivity ( rho _res) at T=O increases linearly with x in the range O<or=x<or=0.07. These facts suggest that the linear term in rho arises from an intrinsic scattering mechanism which is independent of x, and that the substituting zinc atoms act as independent scattering centres, in accordance with Matthiessen's rule for normal metals.