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Spin waves in the Frustrated Kagome Lattice Antiferromagnet KFe3(OH)6(SO4)2

K. Matan·D. Grohol·D. G. Nocera·T. Yildirim·A. B. Harris·S. H. Lee·S. E. Nagler·Y. S. Lee
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Abstract

The spin wave excitations of the ideal S=5/2 Kagome lattice antiferromagnet KFe3(OH)6(SO4)2 have been measured using high-resolution inelastic neutron scattering. We directly observe a flat mode which corresponds to a lifted "zero energy mode," verifying a fundamental prediction for the Kagome lattice. A simple Heisenberg spin Hamiltonian provides an excellent fit to our spin wave data. The antisymmetric Dzyaloshinskii-Moriya interaction is the primary source of anisotropy and explains the low temperature magnetization and spin structure.

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K. Matan, D. Grohol, D. G. Nocera, T. Yildirim, A. B. Harris, S. H. Lee, S. E. Nagler, Y. S. Lee. 2006-02-03. Spin waves in the Frustrated Kagome Lattice Antiferromagnet KFe3(OH)6(SO4)2. https://doi.org/10.1103/physrevlett.96.247201

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