论文标题
五边形材料中的二维Weyl点和淋巴结线及其光学响应
Two-dimensional Weyl points and nodal lines in pentagonal materials and their optical response
论文作者
论文摘要
基于开罗瓷砖的二维五边形结构是具有吸引人物理特性的分层材料家族的基础。在这项工作中，我们介绍了这些五边形材料的基于对称性的电子和光学性质的理论研究。我们提供了支持二元和三元系统五边形结构的空间组的完整分类。通过第一原理计算，分析了它们的电子带结构和动量空间中的局部自旋纹理。我们的结果表明，五边形结构可以在手性晶格中实现，沿着沿Brillouin区域边界的高对称点和淋巴结线固定的Weyl节点；这些变性受到晶体和时间反向对称性的综合作用的保护。此外，我们讨论了某些PENTA材料的线性和非线性光学特征，例如偏移电流，由于淋巴结线和点的存在及其可能的应用，该偏移电流显示出增强。
Two-dimensional pentagonal structures based on the Cairo tiling are the basis of a family of layered materials with appealing physical properties. In this work we present a theoretical study of the symmetry-based electronic and optical properties of these pentagonal materials. We provide a complete classification of the space groups that support pentagonal structures for binary and ternary systems. By means of first-principles calculations, their electronic band structures and the local spin textures in momentum space are analyzed. Our results show that pentagonal structures can be realized in chiral and achiral lattices with Weyl nodes pinned at high-symmetry points and nodal lines along the Brillouin zone boundary; these degeneracies are protected by the combined action of crystalline and time-reversal symmetries. Additionally, we discuss the linear and nonlinear optical features of some penta-materials, such as the shift current, which shows an enhancement due to the presence of nodal lines and points, and their possible applications.
