Effect of On-site Coulomb Repulsion on Ferromagnetic Fluctuations in Heavily Overdoped Cuprates

We theoretically study ferromagnetic (FM) fluctuations in the heavily overdoped region of cuprate superconductors. To explore origin FM fluctuations, we evaluate spin susceptibilities a single-band Hubbard model within fluctuation exchange approximation. Model parameters are derived using Wannierization technique and constrained random phase approximation method based on maximally localized Wannier functions. The calculations reveal that on-site Coulomb interaction decreases with an increase hole doping. This reduction leads to emergence cuprates.