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arXiv · 1106.0615

Single-ion versus two-ion anisotropy in magnetic compounds: A neutron scattering study

A. Furrer·F. Juranyi·K. W. Kraemer·M. Schneider·Th. Straessle
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Abstract

Anisotropy effects can significantly control or modify the ground-state properties of magnetic systems. Yet the origin and the relative importance of the possible anisotropy terms is difficult to assess experimentally and often ambiguous. Here we propose a technique which allows a very direct distinction between single-ion and two-ion anisotropy effects. The method is based on high-resolution neutron spectroscopic investigations of magnetic cluster excitations. This is exemplified for manganese dimers and tetramers in the mixed compounds CsMnxMg1-xBr3 (0.05\leqx\leq0.40). Our experiments provide evidence for a pronounced anisotropy of the order of 3% of the dominant bilinear exchange interaction, and the anisotropy is dominated by the single-ion term. The detailed characterization of magnetic cluster excitations offers a convenient way to unravel anisotropy effects in any magnetic material.

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A. Furrer, F. Juranyi, K. W. Kraemer, M. Schneider, Th. Straessle. 2011-06-03. Single-ion versus two-ion anisotropy in magnetic compounds: A neutron scattering study. https://doi.org/10.1103/physrevb.83.024404

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