de Vries Folkert K, Slizovskiy Sergey, Tomić Petar, Krishna Kumar Roshan, Garcia-Ruiz Aitor, Zheng Giulia, Portolés Elías, Ponomarenko Leonid A, Geim Andre K, Watanabe Kenji, Taniguchi Takashi, Fal'ko Vladimir, Ensslin Klaus, Ihn Thomas, Rickhaus Peter
Laboratory for Solid State Physics, ETH Zürich, Zürich CH-8093, Switzerland.
National Graphene Institute, University of Manchester, Manchester M13 9PL, United Kingdom.
Nano Lett. 2024 Jan 17;24(2):601-606. doi: 10.1021/acs.nanolett.3c03524. Epub 2024 Jan 5.
Electronic spectra of solids subjected to a magnetic field are often discussed in terms of Landau levels and Hofstadter-butterfly-style Brown-Zak minibands manifested by magneto-oscillations in two-dimensional electron systems. Here, we present the semiclassical precursors of these quantum magneto-oscillations which appear in graphene superlattices at low magnetic field near the Lifshitz transitions and persist at elevated temperatures. These oscillations originate from Aharonov-Bohm interference of electron waves following open trajectories that belong to a kagome-shaped network of paths characteristic for Lifshitz transitions in the moire superlattice minibands of twistronic graphenes.
处于磁场中的固体的电子光谱，通常是根据朗道能级以及二维电子系统中磁振荡所表现出的霍夫施塔特蝴蝶型布朗 - 扎克微带来讨论的。在此，我们展示了这些量子磁振荡的半经典先兆，它们出现在低磁场下接近里夫希茨转变的石墨烯超晶格中，并且在高温下依然存在。这些振荡源于电子波的阿哈罗诺夫 - 玻姆干涉，这些电子波沿着属于扭曲石墨烯的莫尔超晶格微带中里夫希茨转变所特有的一种呈 Kagome 形状的路径网络的开放轨迹传播。
