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】

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