2009/03/31 by Steven Hahn, S. E. Hahn, Y. Lee +18 · 1 citation
Chemistry · Materials Science · Physics and Astronomy · #Antiferromagnetism #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Inelastic neutron scattering #Iron-based superconductors research #Magnetism #Materials science #Neutron scattering #Orthorhombic crystal system #Phase (matter) #Phonon #Physics #Quantum mechanics #Scattering #Tetragonal crystal system #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.79.220511
published as Phys. Rev. B 79, 220511(R) (2009) · 4 pages, 3 figures; added additional information and references about spin fluctuations
arxiv created 2009/05/14 · openalex publication_date 2009/06/19 · arxiv updated 2013/11/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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.