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Spin Waves, Phase Separation, and Interphase Boundaries in Double Exchange Magnets

D. I. Golosov
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Abstract

We study a classical double exchange magnet with direct antiferromagnetic superexchange coupling, J, between the localized spins. It is shown that the de-stabilization of the ferromagnetic ground state with increasing J leads to phase separation; the latter always preempts the spin-wave instability (softening of the magnon spectrum). It is also found that the boundaries separating the ferromagnetic and antiferromagnetic areas of the sample tend to be abrupt.

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D. I. Golosov. 2002-10-16. Spin Waves, Phase Separation, and Interphase Boundaries in Double Exchange Magnets. https://doi.org/10.1063/1.1448306

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