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Related papers: Nearly Flat Chern Bands in Moir\'e Superlattices

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It was recently argued that Bernal stacked bilayer graphene (BLG) exposed to a 2D superlattice (SL) potential exhibits a variety of intriguing behaviors [Ghorashi et al., Phys. Rev. Lett. 130, 196201 (2023)]. Chief among them is the…

Mesoscale and Nanoscale Physics · Physics 2024-11-19 Daniel Seleznev , Jennifer Cano , David Vanderbilt

Many graphene moir\'e superlattices host narrow bands with non-zero valley Chern numbers. We provide analytical and numerical evidence for a robust spin and/or valley polarized insulator at total integer band filling in nearly flat bands of…

Strongly Correlated Electrons · Physics 2020-05-13 Cécile Repellin , Zhihuan Dong , Ya-Hui Zhang , T. Senthil

Rhombohedral $N = 3$ trilayer graphene on hexagonal boron nitride (TLG/BN) hosts gate-tunable, valley-contrasting, nearly flat topological bands that can trigger spontaneous quantum Hall phases under appropriate conditions of the valley and…

Mesoscale and Nanoscale Physics · Physics 2021-04-21 David Andres Galeano Gonzalez , Bheema Lingam Chittari , Youngju Park , Jin-Hua Sun , Jeil Jung

Topological flat bands at the Fermi level offer a promising platform to study a variety of intriguing correlated phase of matter. Here we present band engineering in the twisted orbital-active bilayers with spin-orbit coupling. The symmetry…

Mesoscale and Nanoscale Physics · Physics 2022-09-15 Huan Wang , Yadong Jiang , Zhaochen Liu , Jing Wang

We propose a tunable optical setup to engineer topologically nontrivial flat bands in twisted bilayer graphene under circularly polarized light. Using both analytical and numerical calculations, we demonstrate that nearly flat bands can be…

Strongly Correlated Electrons · Physics 2020-12-18 Yantao Li , H. A. Fertig , Babak Seradjeh

We present a theoretical investigation of the emergence of chiral topological superconductivity in small-angle twisted bilayer graphene (tBLG) and twisted double bilayer graphene (tDBLG). Using the low-energy continuum model and…

Mesoscale and Nanoscale Physics · Physics 2025-12-22 Kamalesh Bera , Tanay Nag , Arijit Saha

We use a lowest Landau level model to study the recent observation of an anomalous Hall effect in twisted bilayer graphene. This effective model is rooted in the occurrence of Chern bands which arise due to the coupling between the graphene…

Strongly Correlated Electrons · Physics 2020-04-28 Nick Bultinck , Shubhayu Chatterjee , Michael P. Zaletel

The supermoir\'e lattice, built by stacking two moir\'e patterns, provides a platform for creating flat mini-bands and studying electron correlations. An ultimate challenge in assembling a graphene supermoir\'e lattice is in the…

When monolayer graphene is crystallographically aligned to hexagonal boron nitride (BN), a moir\'e superlattice is formed, producing characteristic satellite Dirac peaks in the electronic band structure. Aligning a second BN layer to…

Graphene-based moire superlattices exhibit novel quantum phenomena driven by pronounced interactions, leading to topological corrected states like orbital Chern insulators exhibiting quantum anomalous Hall effect (QAHE). Typically,…

Mesoscale and Nanoscale Physics · Physics 2025-12-29 Zaizhe Zhang , Xi Chen , Kenji Watanabe , Takashi Taniguchi , Zhida Song , Xiaobo Lu

Two-dimensional atomic crystals can radically change their properties in response to external influences such as substrate orientation or strain, resulting in essentially new materials in terms of the electronic structure. A striking…

We study the electronic structure and band topology of fully relaxed twisted multi-layer graphene (TMLG). Isolated flat bands emerge in TMLG with the number of layers [$M+N$ with $M$ the layer number of the bottom few-layer graphene (FLG)]…

Mesoscale and Nanoscale Physics · Physics 2021-09-22 Xianqing Lin , Haotian Zhu , Jun Ni

Moir\'{e} superlattices in twisted bilayer graphene and transition-metal dichalcogenides have emerged as a powerful tool for engineering novel band structures and quantum phases of two-dimensional quantum materials. Here we investigate…

Quantum Gases · Physics 2021-03-17 Xi-Wang Luo , Chuanwei Zhang

We study the electronic band structure and the topological property of the twisted double bilayer graphene, or a pair of AB-stacked bilayer graphenes rotationally stacked on top of each other. We consider two different arrangements, AB-AB…

Mesoscale and Nanoscale Physics · Physics 2019-06-10 Mikito Koshino

Twisted graphene bilayers show a complex electronic structure, further modified by interaction effects. The main features can be obtained from effective models, which make use a few phenomenological parameters. We analyze the influence of…

Strongly Correlated Electrons · Physics 2019-03-04 Niels R. Walet , Francisco Guinea

Studies on two-dimensional electron systems in a strong magnetic field first revealed the quantum Hall (QH) effect, a topological state of matter featuring a finite Chern number (C) and chiral edge states. Haldane later theorized that Chern…

Fractional quantum anomalous Hall effects realized in twisted bilayer MoTe$_2$ and multilayer-graphene-based moir\'e heterostructures have captured a tremendous growth of interest. In this work, we propose that rhombohedral multilayer…

Mesoscale and Nanoscale Physics · Physics 2025-03-17 Yanran Shi , Bo Xie , Fengfan Ren , Xinyu Cai , Zhongqing Guo , Qiao Li , Xin Lu , Nicolas Regnault , Zhongkai Liu , Jianpeng Liu

We experimentally investigate the band structures of chirally twisted triple bilayer graphene. The new kind of moir\'e structure, formed by three pieces of helically stacked Bernal bilayer graphene, has flat bands at charge neutral point…

Mesoscale and Nanoscale Physics · Physics 2025-01-14 Wenlu Lin , Wenxuan Wang , Shimin Cao , Miao Liang , Lili Zhao , Kenji Watanabe , Takashi Taniguchi , Jinhua Gao , Jianhao Chen , Xiaobo Lu , Yang Liu

The discovery of correlated phases in twisted moir\'e superlattices accelerated the search for low-dimensional materials with exotic properties. A promising approach uses engineered substrates to strain the material. However, designing…

Mesoscale and Nanoscale Physics · Physics 2023-08-25 Md Tareq Mahmud , Dawei Zhai , Nancy Sandler

In bilayer graphene rotationally faulted to theta=1.1 degrees, interlayer tunneling and rotational misalignment conspire to create a pair of low energy flat band that have been found to host various correlated phenomena at partial filling.…

Mesoscale and Nanoscale Physics · Physics 2021-06-21 Yu Saito , Jingyuan Ge , Louk Rademaker , Kenji Watanabe , Takashi Taniguchi , Dmitry A. Abanin , Andrea F. Young