Renormalization of magnetic fluctuations and the in-plane resistivity curvature in the normal state of cuprate superconductors

The temperature dependence of the resistivity ρ(T) in two-dimensional doped antiferromagnet is investigated for different forms of the dynamical spin susceptibility χ(q,ω) taking into account the sum rule: for a mean-field form χmf(q,ω), which allows for the spin mode damping γ and the renormalization of a mean-field spectrum ωq,mf and for a so-called strongly overdamped form χso(q,ω). Doped cuprates are discussed within the single band Kondo lattice model. A strong temperature-dependent scattering anisotropy in the kinetic equation for the carrier distribution function is treated through the density matrix formalism in seven-moment approach. Obtained ρ(T) dependence demonstrates qualitative agreement with experimental data for optimally doped high temperature superconductors. It is found that an damping increase leads to the change of the ρ(T) positive curvature to a liner law of ρ(T) dependence, the use of the strongly overdamped form χso(q,ω) leads to the curvature sign change from a positive one to negative. A spin gap temperature dependence and a renormalization of a mean-field spectrum ωq,mf are of crucial importance for the behavior of ρ(T)