Influence of magnetism on phonons in CaFe2As2 as seen via inelastic x-ray scattering
| Title | Influence of magnetism on phonons in CaFe2As2 as seen via inelastic x-ray scattering |
| Publication Type | Journal Article |
| Year of Publication | 2009 |
| Authors | Hahn SE, Lee Y, Ni N, Canfield PC, Goldman AI, McQueeney RJ, Harmon BN, Alatas A, Leu BM, Alp EE, Chung DY, Todorov IS, Kanatzidis MG |
| Journal Title | Physical Review B |
| Volume | 79 |
| Pages | 220511 |
| Date Published | 06/01 |
| ISBN Number | 1098-0121 |
| Accession Number | ISI:000267699300019 |
| Keywords | ab initio calculations, antiferromagnetic materials, arsenic alloys, calcium alloys, electron spin polarisation, iron alloys, iron-pnictides, magnetic moments, phonon dispersion relations, x-ray scattering |
| Abstract | In the iron pnictides, the strong sensitivity of the iron magnetic moment to the arsenic position suggests a significant relationship between phonons and magnetism. We measured the phonon dispersion of several branches in the high-temperature tetragonal phase of CaFe2As2 using inelastic x-ray scattering on single-crystal samples. These measurements were compared to ab initio calculations of the phonons. Spin-polarized calculations imposing the antiferromagnetic order present in the low-temperature orthorhombic phase dramatically improve agreement between theory and experiment. This is discussed in terms of the strong antiferromagnetic correlations that are known to persist in the tetragonal phase. |
| URL | <Go to ISI>://000267699300019 |
| DOI | 10.1103/Physrevb.79.220511 |
