论文标题
狄拉克半法中的拓扑铰链模式
Topological hinge modes in Dirac semimetals
论文作者
论文摘要
狄拉克半学（DSM）是物质拓扑状态的重要类别。在这里，着眼于频段反转类型的DSM，我们从有效的模型角度研究了它们的边界模式。我们表明，为了正确捕获边界模式，$ k $ - 皮基术语必须包括在有效模型中，这将使表面退化歧管的演变从节点线到节点点。使用第一原理计算，我们证明了该特征和拓扑铰链模式可以在$β$ -CUI中清楚地显示出来。我们将讨论进一步扩展到磁性DSM，并表明时间反转对称性破裂会散布表面带，因此有助于揭示光谱中的铰链模式，这可能对铰链模式的实验检测有益。
Dirac semimetals (DSMs) are an important class of topological states of matter. Here, focusing on DSMs of band inversion type, we investigate their boundary modes from the effective model perspective. We show that in order to properly capture the boundary modes, $k$-cubic terms must be included in the effective model, which would drive an evolution of surface degeneracy manifold from a nodal line to a nodal point. Using first-principles calculations, we demonstrate that this feature and the topological hinge modes can be clearly exhibited in $β$-CuI. We further extend the discussion to magnetic DSMs and show that the time-reversal symmetry breaking can gap out the surface bands and hence help to expose the hinge modes in the spectrum, which could be beneficial for the experimental detection of hinge modes.
