Doping dependence of Fermi surface in high-T_c cuprates studied by model Hartree-Fock calculations

We have investigated doping dependence of Fermi surface, band dispersion, and magnetic structure in high-T_c cuprates by using Hartree-Fock calculation on a Cu 3d–O 2p tight-binding model. In the slightly electron-doped regime, electron pockets emerge around (π,0), which agrees with the photoemission study of Nd_2-xCe_xCuO₄. In the slightly hole-doped regime, hole pockets emerge around (π/2,π/2), which might explain the recent photoemission result of Ca_2-xNa_xCuO₂Cl₂.