论文标题
新颖的拓扑半学系列蝴蝶状的淋巴结线
Novel Family of Topological Semimetals with Butterfly-like Nodal Lines
论文作者
论文摘要
近年来，拓扑半学（TSM）的异国特性引起了极大的关注，并为寻求新的拓扑阶段和物质实现做出了巨大的努力。在这项工作中，我们提出了一个新的TSM家族，该家族携带了前所未有的淋巴结线（NL）景观，该景观由一对同心相交的共面椭圆（CICE）组成。同时，半填充的CICE保证了第二对超越半填充的CICE的存在。这两个CICE都在区域边界处的四倍变性点（FDP）链接。此外，我们确定了在时间逆转不变{\ it无旋转} fermion系统或具有微不足道的旋转轨道偶联（SOC）的跨度系统中，确定了CICE存在的通用标准。因此，在230个空间组（SG）中，有9个是可行的，对于托管CICE的位置中心（BZ）被确定为托管CICE。我们提供了最简单的型号，其中包括SG $ PBAM $（第55号），该模型展示了CICE，以及由双波段内引起的异国情调的互动的鼓头表面状态。最后，我们提出了一系列材料候选者，这些材料像蝴蝶般的cice nls，例如，zrx $ _2 $（x = p，as），gete $ _5 $ _5 $ tl $ _2 $，cyb $ _2 $和al $ _2 $ _2 $ y $ y $ _3 $。
In recent years, the exotic properties of topological semimetals (TSMs) have attracted great attention and significant efforts have been made in seeking for new topological phases and material realization. In this work, we propose a new family of TSMs which harbors an unprecedented nodal line (NL) landscape consisting of a pair of concentric intersecting coplanar ellipses (CICE) at half-filling. Meanwhile, the CICE at half-filling guarantees the presence of a second pair of CICE beyond half-filling. Both CICEs are linked at four-fold degenerate points (FDPs) at zone boundaries. In addition, we identify the generic criteria for the existence of the CICE in a time reversal invariant {\it spinless} fermion system or a spinfull system with negligible spin-orbital coupling (SOC). Consequently, 9 out of 230 space groups (SGs) are feasible for hosting CICE whose location centers in the first Brillouin zone (BZ) are identified. We provide a simplest model with SG $Pbam$ (No. 55) which exhibits CICE, and the exotic intertwined drumhead surface states, induced by double-band-inversions. Finally, we propose a series of material candidates that host butterfly-like CICE NLs, such as, ZrX$_2$ (X=P,As), GeTe$_5$Tl$_2$, CYB$_2$ and Al$_2$Y$_3$.
