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arXiv · 1812.04392

Uniform Perpendicular and Parallel Staggered Susceptibility of Antiferromagnetic Films

Christoph Peter Hofmann
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Abstract

We investigate the thermodynamic behavior of antiferromagnetic films in external magnetic fields oriented perpendicular to the staggered magnetization. Within the systematic effective Lagrangian framework we first calculate the two-point function and the dispersion relation for the two types of magnons up to one-loop order. This allows us to split the two-loop free energy density into a piece that originates from noninteracting dressed magnons, and a second piece that corresponds to the genuine magnon-magnon interaction. We then discuss the low-temperature series for various thermodynamic quantities, including the parallel staggered and uniform perpendicular susceptibilities, and analyze the role of the spin-wave interaction at finite temperature.

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Christoph Peter Hofmann. 2018-12-11. Uniform Perpendicular and Parallel Staggered Susceptibility of Antiferromagnetic Films. https://arxiv.org/abs/1812.04392

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