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arXiv · 1004.2934

Low Energy, Coherent, Stoner-like Excitations in CaFe$_{2}$As$_{2}$

L. Ke·M. van Schilfgaarde·J. J. Pulikkotil·T. Kotani·V. P. Antropov
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Abstract

Using linear-response density-functional theory, magnetic excitations in the striped phase of CaFe$_{2}$As$_{2}$ are studied as a function of local moment amplitude. We find a new kind of excitation: sharp resonances of Stoner-like (itinerant) excitations at energies comparable to the N{é}el temperature, originating largely from a narrow band of Fe $d$ states near the Fermi level, and coexist with more conventional (localized) spin waves. Both kinds of excitations can show multiple branches, highlighting the inadequacy of a description based on a localized spin model.

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BibTeXRIS

L. Ke, M. van Schilfgaarde, J. J. Pulikkotil, T. Kotani, V. P. Antropov. 2010-06-29. Low Energy, Coherent, Stoner-like Excitations in CaFe$_{2}$As$_{2}$. https://doi.org/10.1103/physrevb.83.060404

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