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arXiv · 1207.6688

Excitations and spin correlations near the interface of two three-dimensional Heisenberg antiferromagnets

N. Voropajeva·A. Sherman
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Abstract

Magnetic excitations and spin correlations near the interface of two spin-$\frac12$ Heisenberg antiferromagnets are considered using the spin-wave approximation. When the interaction between boundary spins differs essentially from exchange constants inside the antiferromagnets, quasi-two-dimensional spin waves appear in the near-boundary region. They eject bulk magnons from this region, thereby dividing the antiferromagnets into areas with different magnetic excitations. The decreased dimensionality of the near-boundary modes leads to amplified nearest-neighbor spin correlations in the interface area.

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N. Voropajeva, A. Sherman. 2012-07-28. Excitations and spin correlations near the interface of two three-dimensional Heisenberg antiferromagnets. https://doi.org/10.1016/j.physleta.2012.07.036

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