Antiferromagnetic to ferromagnetic phase transition as a transition to partial ordered spins. Application to $L{a}_{1-x}C{a}_{x}Mn{O}_3$ in the doping range $x\ge 0.50$

N. Karchev

Magnetic state is a partial ordered state if only part of the electrons in the system give contribution to the magnetic order. We study Heisenberg model of two sublattice spin syst…