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arXiv 1807.10271cond-mat.mtrl-sci
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世界上的(高质量)拓扑材料

The (High Quality) Topological Materials In The World

M. G. Vergniory, L. Elcoro, C. Felser, N. Regnault, B. A. Bernevig, Z. Wang

摘要:

拓扑量子化学(TQC)将给定材料的化学和对称结构与其拓扑性质联系起来。该字段将材料的10398个实空间原子极限数据列表,并求解动量空间中电子能带的相容关系。不满足原子极限或能带不满足相容关系的材料是拓扑绝缘体/半金属。我们使用TQC来寻找世界上拓扑化学计量的非磁性“高质量”材料。我们开发了几个代码添加到VASP,可以计算所有的字符的所有对称性在所有高对称点的布里渊区(BZ)。使用TQC,然后我们开发代码来检查哪些材料在ICSD的拓扑。在我们筛选的ICSD数据库中的26938种化学计量材料中,我们发现了2861种拓扑绝缘体(TI)和2936种拓扑半金属(分别为2505和2560个非f电子)。我们的方法是唯一能够表明,没有TI的发现表现出脆弱的拓扑结构。我们将拓扑材料划分为不同的物理类。对于大多数的5797“高质量”拓扑材料,我们计算:拓扑类(等价类的TQC基本带表示-等价于拓扑指数),对称性(ies),保护拓扑类,在高对称点和直接间隙(绝缘体)的表示,和拓扑指数。对于拓扑半金属,我们然后计算系统是否成为一个拓扑绝缘体(其指数/类,我们计算)打破对称性-有用的实验。以这种方式获得了2152个以上的TI。对于几乎所有的5065非f-电子拓扑材料,我们提供的电子能带结构,允许定量属性(间隙,速度)的识别。值得注意的是,我们详尽的结果表明,很大一部分(~ 24%!)自然界中所有材料的拓扑性(通过对“低质量”材料的计算得到证实)。通过威尔逊圈计算,确定了几种新材料的拓扑结构.我们在毕尔巴鄂晶体服务器(BCS)上添加了一个开源代码和最终用户按钮,可以检查任何材料的拓扑结构。我们对每种化合物的化学性质进行了评论,并对“低质量”的ICSD数据进行了抽样,以找到更多的材料。"

英文摘要:

"Topological Quantum Chemistry (TQC) links the chemical and symmetry structure of a given material with its topological properties. This field tabulates the data of the 10398 real-space atomic limits of materials, and solves the compatibility relations of electronic bands in momentum space. A material that is not an atomic limit or whose bands do not satisfy the compatibility relations, is a topological insulator/semimetal. We use TQC to find the topological stoichiometric non-magnetic, "high-quality'' materials in the world. We develop several code additions to VASP which can compute all characters of all symmetries at all high-symmetry points in the Brillouin Zone (BZ). Using TQC we then develop codes to check which materials in ICSD are topological. Out of 26938 stoichiometric materials in our filtered ICSD database, we find 2861 topological insulators (TI) and 2936 topological semimetals (2505 and 2560 non-f electron, respectively). Our method is uniquely capable to show that none of the TI's found exhibit fragile topology. We partition the topological materials in different physical classes. For the majority of the 5797 "high-quality'' topological material, we compute: the topological class (equivalence classes of TQC elementary band representations -- equivalent to the topological index), the symmetry(ies) that protects the topological class, the representations at high symmetry points and the direct gap (for insulators), and the topological index. For topological semimetals we then compute whether the system becomes a topological insulator (whose index/class we compute) upon breaking symmetries -- useful for experiments. 2152 more TI's are obtained in this way. For almost all 5065 non-f-electron topological materials, we provide the electronic band structures, allowing the identification of quantitative properties (gaps, velocities). Remarkably, our exhaustive results show that a large proportion ( ~ 24% !) of all materials in nature are topological (confirmed by calculations of "low-quality'' materials). We confirm the topology of several new materials by Wilson loop calculations. We added an open-source code and end-user button on the Bilbao Crystallographic Server (BCS) which checks the topology of any material. We comment on the chemistry of each compound and sample part of the "low-quality'' ICSD data to find more materials."

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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