Charge-ordered, spin-spiral state in perovskite manganites

Abstract A magnetic phase diagram of the ground state of perovskite manganites is studied in a mean field approximation for the double-exchange model with the nearest-neighbor Coulomb repulsion and superexchange interaction between localized spins. It is shown that a charge-ordered spin-spiral state is stable at the quarter filling and that this state nearly degenerate with the fully polarized ferromagnetic state.