论文标题
节点线和映射以ca $ _2 $为家庭的镜像Chern号码
Nodal lines and mapping to mirror Chern numbers in Ca$_2$As family
论文作者
论文摘要
我们通过组合第一原理计算和紧密结合模型计算来研究CA $ _2 $中材料的拓扑特性，而无需自旋轨道耦合（SOC）。由于计算，我们揭示了CA $ 2_ $由一个绝缘体相和三个节点线相组成，包括相交的淋巴结环相，尽管没有一个阶段之一，其中一个阶段是带有逼真的材料参数。此外，我们讨论引入SOC时，每个节点线阶段都会出现哪种非平凡拓扑不变性。我们还发现了从淋巴结线半学的映射，而没有SOC到具有SOC的拓扑结晶绝缘子。该映射可用于指定先前阶段分类方法给出的候选者的实现拓扑阶段。
We study topological properties of materials in the Ca$_2$As family without spin-orbit coupling (SOC) by combining the first-principles calculation and a tight-binding model calculation. As a result of the calculation, we reveal that the Ca$2_$As family consists of one insulator phase and three nodal line phases including an intersecting nodal ring phase, though one of the phases is not found with realistic material parameters. Additionally, we discuss what kind of nontrivial topological invariants will emerge from each nodal line phase when SOC is introduced. We also find a mapping from a nodal line semimetal without SOC to a topological crystalline insulator with SOC. This mapping can be used to specify the realized topological phase from the candidates given by the previous phase classification method.
