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arXiv · 1011.3831

Itinerant Spin Excitations in SrFe2As2 Measured by Inelastic Neutron Scattering

R. A. Ewings·T. G. Perring·J. Gillett·S. D. Das·S. E. Sebastian·A. E. Taylor·T. Guidi·A. T. Boothroyd
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Abstract

We report inelastic neutron scattering measurements of the magnetic excitations in SrFe2As2, the parent of a family of iron-based superconductors. The data extend throughout the Brillouin zone and up to energies of ~260meV. An analysis with the local-moment J_1-J2 model implies very different in-plane nearest-neighbor exchange parameters along the $a$ and $b$ directions, both in the orthorhombic and tetragonal phases. However, the spectrum calculated from the J1-J2 model deviates significantly from our data. We show that the qualitative features that cannot be described by the J1-J2 model are readily explained by calculations from a 5-band itinerant mean-field model.

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R. A. Ewings, T. G. Perring, J. Gillett, S. D. Das, S. E. Sebastian, A. E. Taylor, T. Guidi, A. T. Boothroyd. 2011-06-16. Itinerant Spin Excitations in SrFe2As2 Measured by Inelastic Neutron Scattering. https://doi.org/10.1103/physrevb.83.214519

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