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arXiv · 1201.2332

Local magnetic anisotropy in BaFe$_2$As$_2$: a polarized inelastic neutron scattering study

N. Qureshi·P. Steffens·S. Wurmehl·S. Aswartham·B. Büchner·M. Braden
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Abstract

The anisotropy of the magnetic excitations in BaFe$_2$As$_2$ was studied by polarized inelastic neutron scattering which allows one to separate the components of the magnetic response. Despite the in-plane orientation of the static ordered moment we find the in-plane polarized magnons to exhibit a larger gap than the out-of-plane polarized ones indicating very strong single-ion anisotropy within the layers. It costs more energy to rotate a spin within the orthorhombic {\it a-b} plane than rotating it perpendicular to the FeAs layers.

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N. Qureshi, P. Steffens, S. Wurmehl, S. Aswartham, B. Büchner, M. Braden. 2012-01-11. Local magnetic anisotropy in BaFe$_2$As$_2$: a polarized inelastic neutron scattering study. https://doi.org/10.1103/physrevb.86.060410

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