论文标题
各向异性的三维量子厅效应和介于介质Weyl半法的磁转运
Anisotropic three-dimensional quantum Hall effect and magnetotransport in mesoscopic Weyl semimetals
论文作者
论文摘要
Weyl Semimetals正在出现，成为各种新型现象的新一类量子材料平台。尤其是，预计由表面费米弧和批量相对论状态制成的Weyl轨道在磁转运中发挥关键作用，甚至导致了三维量子厅效应（QHE）。它在实验和理论上很重要，尽管尚不清楚它是否具有与常规二维QHE相同的现象。我们在磁场下发现了量子运输中的非常规全三维各向异性。当霍尔杆电流从横向到平行相对于Weyl Point Alignment的横向平行时，就会发生强抑制甚至消失，这归因于常规的散装式对应关系。此外，沿着磁场的传输可以表现出从负磁磁性到正磁性的显着逆转。这些结果确立了该QHE系统的独特性，作为一种新颖的三维量子问题。
Weyl semimetals are emerging to become a new class of quantum-material platform for various novel phenomena. Especially, the Weyl orbit made from surface Fermi arcs and bulk relativistic states is expected to play a key role in magnetotransport, leading even to a three-dimensional quantum Hall effect (QHE). It is experimentally and theoretically important although yet unclear whether it bears essentially the same phenomenon as the conventional two-dimensional QHE. We discover an unconventional fully three-dimensional anisotropy in the quantum transport under magnetic field. Strong suppression and even disappearance of QHE occur when Hall-bar current is rotated away from being transverse to parallel with respect to the Weyl point alignment, which is attributed to a peculiar absence of conventional bulk-boundary correspondence. Besides, transport along the magnetic field can exhibit a remarkable reversal from negative to positive magnetoresistance. These results establish the uniqueness of this QHE system as a novel three-dimensional quantum matter.
