发表机构
University of Manchester; National Graphene Institute, University of Manchester; City University of Hong Kong; National University of Singapore; Institute for Functional Intelligent Materials, National University of Singapore（曼彻斯特大学; 国家石墨烯研究所，曼彻斯特大学; 香港城市大学; 新加坡国立大学; 功能智能材料研究所，新加坡国立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究预测了带单层hBN间隔层的超小角度扭转石墨烯多层膜中的光谱和量子输运效应，揭示了层间杂化引起的1/B周期高温磁阻振荡。
AI 中文摘要
基于对带有单层六方氮化硼（hBN）间隔层的小角度扭转石墨烯多层膜中莫尔超晶格特性和层间杂化的分析，我们预测了这些系统中的光谱特征和量子输运效应。在此，我们考虑了扭转双层和带间隔层的双双层结构，讨论了两种堆叠顺序（具有和不具有反演对称性）的双双层，并将自洽哈特里计算的结果与考虑和不考虑面内周期性电荷分布的结果进行比较，为这些石墨烯/hBN/石墨烯莫尔系统提供了计算高效的模型。我们指出了通过面外位移场调节可以增强迷你带出现的参数区间，并在广泛的密度和位移场范围内识别了迷你带边缘和范霍夫奇点。这些系统发生Lifshitz转变，在转变点费米线在莫尔布里渊区形成网络，布朗-扎克振荡在低磁场和高温下汇聚于此。我们在相同的参数空间内分析了层间杂化，讨论了杂化如何影响超高迁移率结构中的面内磁输运，并预测层间杂化的半经典磁振荡可导致电阻率的1/B周期性量子振荡，且该振荡持续至高温。
英文摘要
Based on the analysis of moiré superlattice characteristics and interlayer hybridisation in small-angle twisted graphene multilayers with a monolayer hexagonal boron nitride (hBN) spacer, we predict spectral features and quantum transport effects in these systems. Here, we consider both a twisted bilayer and double bilayers with a spacer, discuss double bilayers in two stacking orders - with and without inversion symmetry - and also compare the results obtained with self-consistent Hartree calculations with and without in-plane periodic charge distribution, offering computationally efficient models for these graphene/hBN/graphene moiré systems. We note parametric intervals where the appearance of minibands can be enhanced by tuning with an out-of-plane displacement field, and identify the miniband edges and van Hove singularities across a broad range of densities and displacement fields. These system host Lifshitz transitions at which the Fermi lines form a network across moiré Brillouin zones, and to which Brown-Zak oscillations converge at low magnetic field and elevated temperatures. We analyse interlayer hybridisation across the same parameter space, discuss how hybridisation affects in-plane magneto-transport in ultra-high-mobility structures, and predict that semiclassical magneto-oscillations of interlayer hybridisation can lead to 1/B-periodic quantum oscillations of resistivity persistent to high temperature.
Comments21 pages, 12 figures
