论文标题
电子孔杂交间隙和山谷石墨烯中电子孔杂交间隙和山谷分裂的磁性振荡
Magnetoconductance Oscillations in Electron-hole Hybridization Gaps and Valley Splittings in Tetralayer Graphene
论文作者
论文摘要
我们研究了Bernal堆叠四边形石墨烯上的磁转运，其带状结构由两个具有不同有效质量的大型子带组成。在有限的位移场下，我们仅在轻质量子带中观察到山谷水平（LLS）的山谷分裂，这与紧密结合模型一致。在低密度下，我们发现散装间隙中意外的磁磁振荡起源于跨四环石墨烯中带反转引起的电子样和类似孔的LL之间的一系列杂交。与微不足道的LL量化差距相反，这些倒置杂交差距可以导致边缘状态数量的变化，这解释了观察到的振荡。
We investigate magnetotransport on Bernal-stacked tetralayer graphene whose band structure consists of two massive subbands with different effective masses. Under a finite displacement field, we observe valley splitting of Landau levels (LLs) only in the light-mass subband, consistent with a tight-binding model. At low density, we find unexpected magnetoconductance oscillations in bulk gaps which originate from a series of hybridizations between electron-like and hole-like LLs due to band inversion in tetralayer graphene. In contrast to a trivial LL quantization gap, these inverted hybridization gaps can lead to a change in number of edge states which explains the observed oscillations.
