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Boundary Energies and the Geometry of Phase Separation in Double--Exchange Magnets

D. I. Golosov·D. Orgad
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Abstract

We calculate the energy of a boundary between ferro- and antiferromagnetic regions in a phase separated double-exchange magnet in two and three dimensions. The orientation dependence of this energy can significantly affect the geometry of the phase-separated state in two dimensions, changing the droplet shape and possibly stabilizing a striped arrangement within a certain range of the model parameters. A similar effect, albeit weaker, is also present in three dimensions. As a result, a phase-separated system near the percolation threshold is expected to possess intrinsic hysteretic transport properties, relevant in the context of recent experimental findings.

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D. I. Golosov, D. Orgad. 2006-08-29. Boundary Energies and the Geometry of Phase Separation in Double--Exchange Magnets. https://doi.org/10.1103/physrevb.74.104403

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