论文标题
2D屈曲蜂窝晶格的拓扑声子分析：真实材料的应用
Topological phonon analysis of the 2D buckled honeycomb lattice: an application to real materials
论文作者
论文摘要
通过群体理论，拓扑量子化学，第一原理和蒙特卡洛计算，我们分析了2D弯曲的蜂窝晶状体声子光谱的拓扑。以纯晶体结构为输入，我们表明可能有11个不同的阶段，其中五个必然根据拓扑量子化学具有非平凡的拓扑结构。在分析模型中，使用威尔逊环路（Wilson Loops）也将其中的另外四个鉴定为拓扑，其中包括所有对称性允许力常数高达第三个最近的邻居，从而使总共九个拓扑阶段。然后，我们在此结构中计算Si，ge，p，as和sb的二维晶体的Ab intib shit子光谱，并构造其相图。尽管在分析模型中发现的拓扑阶段很大比例，但所有晶体都处于微不足道的阶段。通过使用蒙特卡洛计算分析力常数空间，我们阐明了为什么在具有这种晶体结构的真实材料中很难在物理上很难实现拓扑声子。
By means of group theory, topological quantum chemistry, first-principles and Monte Carlo calculations, we analyze the topology of the 2D buckled honeycomb lattice phonon spectra. Taking the pure crystal structure as an input, we show that eleven distinct phases are possible, five of which necessarily have non-trivial topology according to topological quantum chemistry. Another four of them are also identified as topological using Wilson loops in an analytical model that includes all the symmetry allowed force constants up to third nearest neighbors, making a total of nine topological phases. We then compute the ab initio phonon spectra for the two-dimensional crystals of Si, Ge, P, As and Sb in this structure and construct its phase diagram. Despite the large proportion of topological phases found in the analytical model, all of the crystals lie in a trivial phase. By analyzing the force constants space using Monte Carlo calculations, we elucidate why topological phonon phases are physically difficult to realize in real materials with this crystal structure.
