Effect of magnetism on lattice dynamics in SrFe2As2 using high-resolution inelastic x-ray scattering
Effect of magnetism on lattice dynamics in SrFe2As2 using high-resolution inelastic x-ray scattering
复制标题
使用高分辨率非弹性 X 射线散射研究磁性对 SrFe2As2 晶格动力学的影响
DOI：
10.1103/physrevb.93.020301
复制
发表时间：
2016
影响因子：
3.7
通讯作者：
and A. Q. R. Baron
中科院分区：
文献类型：
--
作者：
N. Murai;T. Fukuda;T. Kobayashi;M. Nakajima;H. Uchiyama;D. Ishikawa;S. Tsutsui;H. Nakamura;M. Machida;S. Miyasaka;S. Tajima;and A. Q. R. Baron
通过非弹性 X 射线散射测量的非孪生晶体的声子光谱显示出伴随 200 K 磁结构转变的清晰的各向异性。我们使用磁性 DFT 计算对模式分裂进行建模，包括可归因于磁波动的力常数各向异性的现象学减少。这是该材料中适用于反铁磁有序相和顺磁相的声子通用模型的起点。使用该模型、测量到的下面磁相分裂以及测量到的声子线宽，我们将上面的平均磁涨落频率的下限设置为 210 K。
Phonon spectra of detwinnedcrystals, 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, and the measured phonon linewidth, we set a lower bound on the mean magnetic fluctuation frequency aboveat 210 K.