Wang Zihao, Wang Yi Bo, Yin J, Tóvári E, Yang Y, Lin L, Holwill M, Birkbeck J, Perello D J, Xu Shuigang, Zultak J, Gorbachev R V, Kretinin A V, Taniguchi T, Watanabe K, Morozov S V, Anđelković M, Milovanović S P, Covaci L, Peeters F M, Mishchenko A, Geim A K, Novoselov K S, Fal'ko Vladimir I, Knothe Angelika, Woods C R
Department of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
Institute of Nano Science, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Sci Adv. 2019 Dec 20;5(12):eaay8897. doi: 10.1126/sciadv.aay8897. eCollection 2019 Dec.
When two-dimensional (2D) atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals may influence each other's properties. Of particular interest is when the two crystals closely match and a moiré pattern forms, resulting in modified electronic and excitonic spectra, crystal reconstruction, and more. Thus, moiré patterns are a viable tool for controlling the properties of 2D materials. However, the difference in periodicity of the two crystals limits the reconstruction and, thus, is a barrier to the low-energy regime. Here, we present a route to spectrum reconstruction at all energies. By using graphene which is aligned to two hexagonal boron nitride layers, one can make electrons scatter in the differential moiré pattern which results in spectral changes at arbitrarily low energies. Further, we demonstrate that the strength of this potential relies crucially on the atomic reconstruction of graphene within the differential moiré super cell.
当二维（2D）原子晶体彼此靠近形成范德华异质结构时，相邻的晶体可能会相互影响对方的性质。特别令人感兴趣的是，当两种晶体紧密匹配并形成莫尔图案时，会导致电子和激子光谱的改变、晶体重构等等。因此，莫尔图案是控制二维材料性质的一种可行工具。然而，两种晶体周期性的差异限制了重构，因此是低能区的一个障碍。在这里，我们提出了一种在所有能量下进行光谱重构的方法。通过使用与两个六方氮化硼层对齐的石墨烯，可以使电子在差分莫尔图案中散射，从而在任意低能量下产生光谱变化。此外，我们证明了这种势的强度关键取决于差分莫尔超胞内石墨烯的原子重构。
