Magnetism-dependent phonon anomaly in LaFeAsO observed via inelastic x-ray scattering Hahn, S. Lograsso, Thomas Tucker, Gregory Yan, J.-Q. Said, A. Leu, B. McCallum, R. Alp, E. Lograsso, Thomas McQueeney, Robert Harmon, Bruce
dc.contributor.department Ames Laboratory 2018-02-13T14:27:04.000 2020-06-29T23:27:29Z 2020-06-29T23:27:29Z Tue Jan 01 00:00:00 UTC 2013 2013-09-20 2013-03-27
dc.description.abstract <p>The phonon dispersion was measured at room temperature along (0,0,L) in the tetragonal phase of LaFeAsO using inelastic x-ray scattering. Spin-polarized first-principles calculations imposing various types of antiferromagnetic order are in better agreement with the experimental results than nonmagnetic calculations, although the measurements were made well above the magnetic ordering temperature, T<sub>N</sub>. Splitting observed between two A<sub>1g</sub> phonon modes at 22 and 26 meV is only reproduced in spin-polarized calculations. Magnetostructural effects similar to those observed in the AFe<sub>2</sub>As<sub>2</sub> (A=Ca,Sr,Ba,Eu) materials are present in LaFeAsO. The inclusion of Fe spin is necessary to find reasonable agreement of the calculations with the measured spectrum well above T<sub>N</sub>. On-site Fe and As force constants show significant softening compared to nonmagnetic calculations, however an investigation of the real-space force constants associates the magnetoelastic coupling with a complex renormalization instead of softening of a specific pairwise force.</p>
dc.description.comments <p>This article is from <em>Physical Review B </em>87 (2013): 104518, doi:<a href="" target="_blank">10.1103/PhysRevB.87.104518</a>.</p>
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dc.identifier archive/
dc.identifier.articleid 1033
dc.identifier.contextkey 4609042
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath ameslab_pubs/41
dc.language.iso en
dc.source.bitstream archive/|||Sat Jan 15 00:09:12 UTC 2022
dc.source.uri 10.1103/PhysRevB.87.104518
dc.subject.disciplines Condensed Matter Physics
dc.subject.disciplines Materials Science and Engineering
dc.subject.disciplines Metallurgy
dc.subject.keywords Physics and Astronomy
dc.title Magnetism-dependent phonon anomaly in LaFeAsO observed via inelastic x-ray scattering
dc.type article
dc.type.genre article
dspace.entity.type Publication
relation.isAuthorOfPublication 316ee29f-99a9-49bc-a048-0f43caf97aa5
relation.isOrgUnitOfPublication 25913818-6714-4be5-89a6-f70c8facdf7e
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