论文标题
在手性拓扑半学PTGA中观察具有最大Chern数的巨型旋转式费米 - arc
Observation of giant spin-split Fermi-arc with maximal Chern number in the chiral topological semimetal PtGa
论文作者
论文摘要
非肌形性手性拓扑晶体寄主外来的多fermions及其相关的费米弧形旋转并在高对称中心和表面角臂之间遍布整个布里群区域。然而，理论上提出的最大切恩数的Fermi-Arc分裂和实现在很大程度上取决于自旋轨道耦合（SOC）强度。在目前的工作中，我们研究了一种新的手性晶体PTGA的拓扑状态，PTGA的拓扑状态在迄今为止所有据报道的手性晶体中具有最强的SOC。通过使用高分辨率角度分辨的光发射光谱，量子振荡测量和最新的从头开始计算进行的全面研究，我们报告了Fermi Arcs和Bulk State的巨大SOC诱导的分裂。因此，这项研究通过实验证实了等于| 4 |的最大Chern数的实现。在多率费米子系统中，第一次提供了一个平台，可以在光学实验中观察大量量化的光藻电流。
Non-symmorphic chiral topological crystals host exotic multifold fermions, and their associated Fermi arcs helically wrap around and expand throughout the Brillouin zone between the high-symmetry center and surface-corner momenta. However, Fermi-arc splitting and realization of the theoretically proposed maximal Chern number rely heavily on the spin-orbit coupling (SOC) strength. In the present work, we investigate the topological states of a new chiral crystal, PtGa, which has the strongest SOC among all chiral crystals reported to date. With a comprehensive investigation using high-resolution angle-resolved photoemission spectroscopy, quantum-oscillation measurements, and state-of-the-art ab initio calculations, we report a giant SOC-induced splitting of both Fermi arcs and bulk states. Consequently, this study experimentally confirms the realization of a maximal Chern number equal to |4| for the first time in multifold fermionic systems, thereby providing a platform to observe large-quantized photogalvanic currents in optical experiments.
