Effect of magnetism on lattice dynamics in SrFe2As2 using high-resolution inelastic x-ray scattering | |
Article | |
关键词: TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; IRON-PNICTIDES; SUPERCONDUCTORS; TRANSITION; ANISOTROPY; METALS; MODE; | |
DOI : 10.1103/PhysRevB.93.020301 | |
来源: SCIE |
【 摘 要 】
Phonon spectra of detwinned SrFe2As2 crystals, as measured by inelastic x-ray scattering, show clear anisotropy accompanying the magnetostructural transition at 200 K. We model the mode splitting using magnetic DFT calculations, including a phenomenological reduction in force-constant anisotropy that can be attributed to magnetic fluctuations. This serves as a starting point for a general model of phonons in this material applicable to both the antiferromagnetically ordered phase and the paramagnetic phase. Using this model, the measured splitting in the magnetic phase below T-N, and the measured phonon linewidth, we set a lower bound on the mean magnetic fluctuation frequency above T-N at 210 K.
【 授权许可】
Free