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Anisotropic Hubbard model on a triangular lattice -- spin dynamics in Ho Mn O_3

Saptarshi Ghosh·Avinash Singh
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Abstract

The recent neutron-scattering data for spin-wave dispersion in $\rm Ho Mn O_3$ are well described by an anisotropic Hubbard model on a triangular lattice with a planar (XY) spin anisotropy. Best fit indicates that magnetic excitations in $\rm Ho Mn O_3$ correspond to the strong-coupling limit $U/t > \sim 15$, with planar exchange energy $J=4t^2/U \simeq 2.5$meV and planar anisotropy $ΔU \simeq 0.35$meV.

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Saptarshi Ghosh, Avinash Singh. 2006-01-06. Anisotropic Hubbard model on a triangular lattice -- spin dynamics in Ho Mn O_3. https://doi.org/10.1007/s12043-008-0014-3

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