A model of resonant Raman scattering via magnetic exciton in ferromagnetic phase

A semi-localized magneticd exciton model is proposed to explain the strong magnetic field dependence of the resonant Raman scattering observed in Eu-chalcogenides in ferro-magnetic phase. Choosing, in comparison with magneto-optical experiment, a single intermediate energy level in which all the spin and orbital angular momenta couple parallel, the observed frequency-, polarization- and magnetic field dependences are explained quantitatively in molecular field approximation. The discrepancy in the temperature dependence is discussed in terms of the short range order and the neglected intermediate energy levels.