Antiferromagnetic Dispersion Relations and Nature of Magnon Pressure

Christoph P. Hofmann

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arXiv · 2009.06584

Antiferromagnetic Dispersion Relations and Nature of Magnon Pressure

Christoph P. Hofmann

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Abstract

We derive higher-order corrections in the magnon dispersion relations for two- and three-dimensional antiferromagnets exposed to magnetic and staggered fields that are mutually aligned. "Dressing" the magnons is the prerequisite to separate the low-temperature representation of the pressure into a piece due to noninteracting magnons and a piece that corresponds to the magnon-magnon interaction. Both in two and three spatial dimensions, the interaction in the pressure turns out to be attractive. While concrete figures refer to the spin-$\frac{1}{2}$ square-lattice and the spin-$\frac{1}{2}$ simple cubic lattice antiferromagnet, our results are valid for arbitrary bipartite geometry.

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Christoph P. Hofmann. 2020-09-14. Antiferromagnetic Dispersion Relations and Nature of Magnon Pressure. https://arxiv.org/abs/2009.06584

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