论文标题
拓扑结构绝缘子SMB $ _6 $（001）的表面电子状态中散装各向同性的分解
Breakdown of bulk-projected isotropy in surface electronic states of topological Kondo insulator SmB$_6$(001)
论文作者
论文摘要
在这十年中，已经对二维（2D）表面电子状态的拓扑和旋转轨道极化进行了广泛的研究。他们对它们的主要兴趣之一是他们与批量（3D）电子状态的平等关系的密切关系。在这种情况下，表面通常被视为散装晶体的简单截断。在这里，我们显示了近孔绝缘子SMB $ _6 $的拓扑表面状态（TSSS）中与散装相关的面内旋转对称性的分解。在附近SMB $ _6 $（001） - $ p $（2 $ \ times $ 2）表面表明TSSS是各向异性的，而Fermi缺乏四倍的旋转对称性。该结果强调了表面原子结构的重要作用，即使在TSS中也是如此。此外，它表明，表面原子结构的工程可以提供新的途径，以在TSS之间量身定制各种特性，例如各向异性表面电导率，表面费米轮廓的嵌套或2D互惠空间中Van Hove单数的数量和位置。
The topology and spin-orbital polarization of two-dimensional (2D) surface electronic states have been extensively studied in this decade. One major interest in them is their close relationship with the parities of the bulk (3D) electronic states. In this context, the surface is often regarded as a simple truncation of the bulk crystal. Here we show breakdown of the bulk-related in-plane rotation symmetry in the topological surface states (TSSs) of the Kondo insulator SmB$_6$. Angle-resolved photoelectron spectroscopy (ARPES) performed on the vicinal SmB$_6$(001)-$p$(2$\times$2) surface showed that TSSs are anisotropic and that the Fermi contour lacks the fourfold rotation symmetry maintained in the bulk. This result emphasizes the important role of the surface atomic structure even in TSSs. Moreover, it suggests that the engineering of surface atomic structure could provide a new pathway to tailor various properties among TSSs, such as anisotropic surface conductivity, nesting of surface Fermi contours, or the number and position of van Hove singularities in 2D reciprocal space.
