Peculiar atomic dynamics in liquid GeTe with asymmetrical bonding: Observation by inelastic x-ray scattering
Peculiar atomic dynamics in liquid GeTe with asymmetrical bonding: Observation by inelastic x-ray scattering
复制标题
具有不对称键合的液态 GeTe 中的特殊原子动力学：非弹性 X 射线散射观察
DOI：
10.1103/physrevb.97.174203
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发表时间：
2018
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：
M. Inui;A. Koura;Y. Kajihara;S. Hosokawa;A. Chiba;K. Kimura;F. Shimojo;S. Tsutsui;and A. Q. R. Baron
用非弹性x射线散射研究了液体Gete中的集体动力学。动力结构因子表现出明显的非弹性激励。低激发能随浓度的增加而弥散，这与纵声激发的行为一致。色散曲线在伪布里渊区边界附近有一个平顶区域，类似于在液体Bi[Inui，Phys]中观察到的情况。B修订版92,054206(2015)PRBMDO1098-012110.1103/PhysRevB.92.054206].动力结构因子表现为低频激励，其与纵声模的耦合对平顶色散起重要作用。从这些结果可以推断，液体GeTe中的原子动力学受到类似于液体Bi的Peierls扭曲的强烈影响。通过比较激发能和准弹性线宽的动量传递与我们自己的分子动力学模拟得到的部分结构因子的关系，发现准弹性和非弹性组分分别与Te-Te和Ge-(Ge，Te)部分结构因子相关。
Collective dynamics in liquid GeTe was investigated by inelastic x-ray scattering at. The dynamic structure factor shows clear inelastic excitations. The excitation energies at lowdisperse with increasing, consistent with the behavior of a longitudinal-acoustic excitation. The dispersion curve has a flat-topped region around the pseudo-Brillouin-zone boundary, similar to what is observed in liquid Bi [Inui , Phys. Rev. B 92, 054206 (2015)PRBMDO1098-012110.1103/PhysRevB.92.054206]. The dynamic structure factor shows a low-frequency excitation, and its coupling with the longitudinal-acoustic mode plays an important role for a flat-topped dispersion. From these results, it is inferred that atomic dynamics in liquid GeTe is strongly affected by a Peierls distortion similar to liquid Bi. By comparing the momentum transfer dependence of the excitation energy and quasielastic linewidth to partial structure factors obtained by our ownab initiomolecular dynamics simulation for liquid GeTe, the quasielastic and inelastic components were found to be correlated with Te-Te and Ge-(Ge,Te) partial structure factors, respectively.