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Magnetic Structure and Spin Waves in the Kagomé Jarosite compound ${\bf KFe_3(SO_4)_2(OH)_6}$

T. Yildirim·A. B. Harris
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Abstract

We present a detailed study of the magnetic structure and spin waves in the Fe jarosite compound ${\rm KFe_3(SO_4)_2(OH)_6}$ for the most general Hamiltonian involving one- and two-spin interactions which are allowed by symmetry. We compare the calculated spin-wave spectrum with the recent neutron scattering data of Matan {\it et al.} for various model Hamiltonians which include, in addition to isotropic Heisenberg exchange interactions between nearest ($J_1$) and next-nearest ($J_2$) neighbors, single ion anisotropy and Dzyaloshinskii-Moriya (DM) interactions. We concluded that DM interactions are the dominant anisotropic interaction, which not only fits all the splittings in the spin-wave spectrum but also reproduces the small canting of the spins out of the Kagomé plane. A brief discussion of how representation theory restricts the allowed magnetic structure is also given.

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T. Yildirim, A. B. Harris. 2006-03-10. Magnetic Structure and Spin Waves in the Kagomé Jarosite compound ${\bf KFe_3(SO_4)_2(OH)_6}$. https://doi.org/10.1103/physrevb.73.214446

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