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Double exchange magnets: Spin-dynamics in the paramagnetic phase

Peter Horsch·Janez Jaklic·Frank Mack
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Abstract

The electronic structure of perovskite manganese oxides is investigated in terms of a Kondo lattice model with ferromagnetic Hund coupling and antiferromagnetic exchange between $t_{2g}$-spins using a finite temperature diagonalization technique. Results for the dynamic structure factor are consistent with recent neutron scattering experiments for the bilayer manganite La$_{1.2}$Sr$_{1.8}$Mn$_2$O$_7$ . The susceptibility shows Curie-Weiss behaviour and is used to derive a phase diagram. In the paramagnetic phase carriers are characterized as ferromagnetic polarons in an antiferromagnetic spin liquid.

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Peter Horsch, Janez Jaklic, Frank Mack. 1997-08-01. Double exchange magnets: Spin-dynamics in the paramagnetic phase. https://doi.org/10.1103/physrevb.59.r14149

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