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arXiv · 1006.5192

Spin wave resonances in antiferromagnets

Abstract

Spin wave resonances with enormously large wave numbers corresponding to wave vectors 10^5-10^6 cm^{-1} are observed in thin plates of FeBO3. The study of spin wave resonances allows one to obtain information about the spin wave spectrum. The temperature dependence of a non-uniform exchange constant is determined for FeBO3. Considerable softening of the magnon spectrum resulting from the interaction of magnons, is observed at temperatures above 1/3 of the Neel temperature. The excitation level of spin wave resonances is found to depend significantly on the inhomogeneous elastic distortions artificially created in the sample. A theoretical model to describe the observed effects is proposed.

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BibTeXRIS

H. -A. Krug von Nidda, L. E. Svistov, L. A. Prozorova. 2010-06-27. Spin wave resonances in antiferromagnets. https://doi.org/10.1063/1.3490859

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