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arXiv · cond-mat/9903039

Crystal Field, Magnetic Anisotropy and Excitations in Rare-Earth Hexaborides

Gennadi Uimin·Wolfram Brenig
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Abstract

We clarify the role of crystalline electric field (CEF) induced magnetic anisotropy in the ground state and spin-wave spectrum of cubic rare-earth materials with dominating isotropic magnetic exchange interactions. In particular we study the hexaboride NdB_6 which is shown to exhibit strong spin-quadrupolar coupling. The CEF scheme is analyzed and a non-collinear magnetization response is found. The spin orientation in the antiferromagnetically ordered ground-state is identified. Moreover, the spin excitations are evaluated and in agreement with inelastic neutron scattering a suppression of one of the two magnetic modes in the strong-coupling regime is predicted.

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Gennadi Uimin, Wolfram Brenig. 1999-03-02. Crystal Field, Magnetic Anisotropy and Excitations in Rare-Earth Hexaborides. https://doi.org/10.1103/physrevb.61.60

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