论文标题
金属 - 韦尔半叠界面的倒置对称性和界面诱导的自旋偏振化
Broken Inversion Symmetry and Interface-induced Spin-polarization for metal-Weyl semimetal stacked interfaces
论文作者
论文摘要
Weyl Semimetal Taas是无质量的Weyl Fermions的友善宿主，自发缺乏时间反转和反转对称性，因此在拓扑上稳定的Weyl节点效果，类似于动量空间中的磁单孔。以前的实验分析表明，大量TAA的接近零自旋极化在非磁金属的点接触存在下经历了提升，以及尖端诱导的超导性的相关现象，从而使大区域堆叠的Taas与Au和Au和Ag和Ag等高分子的Taas相关。这些界面系统上的第一原理计算表明了界面诱导的自旋化和接触诱导的传输自旋极化的增量。与单个界面相反，对于堆叠系统，系统的倒置对称性引入了z方向带散射，从而导致一系列能量分离的Weyl锥。观察到TAAS/AG和TAAS/AU堆叠界面的Weyl锥分别为I型和I型II性质。因此，当前的研究表明了从非磁性金属和I型Weyl成分的两种不同类型的自旋极化Weyl系统的设计。
Weyl semimetal TaAs, a congenial host to the massless Weyl fermions, spontaneously lacks the time-reversal and the inversion symmetry and thus effectuates topologically stable Weyl nodes, resembling magnetic monopoles in momentum space. Former experimental analysis had revealed that the near-zero spin-polarization of bulk TaAs experiences a boost in presence of point-contacts of non-magnetic metals along with the associated phenomena of tip-induced superconductivity, providing the impetus to study the large-area stacked interfaces of TaAs with Noble metals like Au and Ag. First-principles calculations on these interfacial systems have manifested an increment of the interface-induced spin-polarization and contact-induced transport spin-polarization. In contrast to the single interface, for stacked system, the broken inversion symmetry of the system introduces a z-directional band-dispersion resulting in an energetically separated series of Weyl cones. The Weyl cones for TaAs/Ag and TaAs/Au stacked interfaces are observed to be of type-I and type-II nature respectively. Thus, the current study demonstrates the designing of two different types of spin-polarized Weyl systems from non-magnetic metal and type I Weyl components.
