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Theory of spin wave excitations of metallic A-type antiferromagnetic manganites

G. Jackeli·N. B. Perkins·N. M. Plakida
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Abstract

The spin dynamic of the metallic A-type antiferromagnetic manganites is studied. An effective nearest-neighbour Heisenberg spin wave dispersion is derived from the double exchange model taking into account the superexchange interaction between the core spins. The result of inelastic neutron scattering experiment on ${Nd}_{0.45}{Sr}_{0.55}{Mn} {O}_{3}$ is qualitatively reproduced. Comparing theory with experimental data two main parameters of the model: nearest-neighbour electron transfer amplitude and superexchange coupling between the core spins are estimated.

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G. Jackeli, N. B. Perkins, N. M. Plakida. 2001-06-24. Theory of spin wave excitations of metallic A-type antiferromagnetic manganites. https://doi.org/10.1103/physrevb.64.092403

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