论文标题
使用高度极订单来重建来自晶格动力学的压电中的声速
Using high multipolar orders to reconstruct the sound velocity in piezoelectrics from lattice dynamics
论文作者
论文摘要
声子结构上的信息对于预测材料的许多热力学特性，例如热传输系数至关重要。高度精确的声子分散曲线原则上可以在密度功能扰动理论（DFPT）的框架中计算出来。但是，在压电材料的情况下，建立的技术可能会遇到麻烦（甚至在灾难性上失败），那里的声学分支几乎不会再现物理上正确的声音速度。在这里，我们确定原子之间高阶多极相互作用的罪魁祸首，并演示了解决上述问题的有效程序。我们的策略大大提高了压电晶体中扰动晶状体 - 动力计算的预测能力，并且可以直接实现材料数据库的高通量生成。
Information over the phonon band structure is crucial to predicting many thermodynamic properties of materials, such as thermal transport coefficients. Highly accurate phonon dispersion curves can be, in principle, calculated in the framework of density-functional perturbation theory (DFPT). However, well-established techniques can run into trouble (or even catastrophically fail) in the case of piezoelectric materials, where the acoustic branches hardly reproduce the physically correct sound velocity. Here we identify the culprit in the higher-order multipolar interactions between atoms, and demonstrate an effective procedure that fixes the aforementioned issue. Our strategy drastically improves the predictive power of perturbative lattice-dynamical calculations in piezoelectric crystals, and is directly implementable for high-throughput generation of materials databases.
