Magnetization behavior and metamagnetic transitions in electron-doped manganites induced by a strong magnetic field

The behavior of magnetization M of the R(x)A(1-x)MnO3 manganites (R = La, Pr, Nd, Sm, etc., A = Ca, Sr, Ba) in the electron doping region (x less than 0.4) is studied as a function of external magnetic field H. The M(H) relations for homogeneous magnetic structures are obtained by performing band calculations in the double-exchange model. Three different types of magnetization behavior corresponding to three electron concentration ranges (x less than 0.14, x in the range 0.14 to 0.27, x greater than 0.27) are revealed. The M(H) relations are interpreted in terms of the phase diagram for the homogeneous ground state of the manganites calculated for H = 0, and the results agree qualitatively with experimental data on the magnetization of Sm(x)Ca(1-x)MnO3.