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Related papers: Integrability in the chiral model of magic angles

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The Bistritzer-MacDonald (BM) model, introduced in \cite{Bistritzer2011}, attempts to capture the electronic properties of twisted bilayer graphene (TBG), even at incommensurate twist angles, by an effective periodic model over the bilayer…

Mesoscale and Nanoscale Physics · Physics 2023-03-29 Alexander B. Watson , Tianyu Kong , Allan H. MacDonald , Mitchell Luskin

We show that the insulating states of magic-angle twisted bilayer graphene support a series of collective modes corresponding to local particle-hole excitations on triangular lattice sites. Our theory is based on a continuum model of the…

Strongly Correlated Electrons · Physics 2021-07-09 Ajesh Kumar , Ming Xie , A. H. MacDonald

The interplay between strong electron-electron interactions and band topology can lead to novel electronic states that spontaneously break symmetries. The discovery of flat bands in magic-angle twisted bilayer graphene (MATBG) with…

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

We analyze a description of twisted graphene bilayers, that incorporates deformation of the layers due to the nature modern interlayer potentials, and a modification of the hopping parameters between layers in the light of the classic…

Strongly Correlated Electrons · Physics 2019-05-29 Francisco Guinea , Niels R. Walet

We study the degree of band flatness and anisotropic quantum geometry in magic-angle twisted bilayer graphene by varying the twist angle and the lattice relaxation through optical conductivity. We show that the degree of band flatness and…

Mesoscale and Nanoscale Physics · Physics 2026-05-22 Pok Man Chiu

The interplay of twist and strain in bilayer graphene enables the formation of moir\'e patterns and narrow bands that host correlated and topological phases. While magic-angle twisted bilayer graphene has been widely studied, strain…

Mesoscale and Nanoscale Physics · Physics 2026-03-10 Federico Escudero , Dong Wang , Pierre A. Pantaleón , Shengjun Yuan , Francisco Guinea , Zhen Zhan

The interplay between interlayer van der Waals interaction and intralayer lattice distortion can lead to structural reconstruction in slightly twisted bilayer graphene (TBG) with the twist angle being smaller than a characteristic angle…

Mesoscale and Nanoscale Physics · Physics 2020-07-07 Yi-Wen Liu , Ying Su , Xiao-Feng Zhou , Long-Jing Yin , Chao Yan , Si-Yu Li , Wei Yan , Sheng Han , Zhong-Qiu Fu , Yu Zhang , Qian Yang , Ya-Ning Ren , Lin He

Electron interactions in quantum materials fundamentally shape their energy bands and, with them, the material's most intriguing quantum phases. Magic angle twisted bilayer graphene (MATBG) has emerged as a model system, where flat bands…

Mesoscale and Nanoscale Physics · Physics 2025-06-27 J. Xiao , A. Inbar , J. Birkbeck , N. Gershon , Y. Zamir , T. Taniguchi , K. Watanabe , E. Berg , S. Ilani

We investigate the Twisted Bilayer Graphene (TBG) model to obtain an analytic understanding of its energetics and wavefunctions needed for many-body calculations. We provide an approximation scheme which first elucidates why the BM…

Mesoscale and Nanoscale Physics · Physics 2022-04-29 B. Andrei Bernevig , Zhi-Da Song , Nicolas Regnault , Biao Lian

Twisted bilayer graphene with tiny rotation angles have drawn significant attention due to the observation of the unconventional superconducting and correlated insulating behaviors. In this paper, we employ a full tight-binding model to…

Mesoscale and Nanoscale Physics · Physics 2021-03-24 Xueheng Kuang , Zhen Zhan , Shengjun Yuan

Magic-angle twisted bilayer graphene (TBG) with its flat bands provides a rich platform for exploring emergent electronic orders. Similarly, periodically buckled monolayer graphene has been proposed as a tunable alternative for realizing…

Mesoscale and Nanoscale Physics · Physics 2025-10-16 Jannes van Poppelen , Annica M. Black-Schaffer

Motivated by the recent observation of correlated insulator states and unconventional superconductivity in twisted bilayer graphene, we study the dependence of electron correlations on the twist angle and reveal the existence of strong…

Strongly Correlated Electrons · Physics 2019-09-18 Zachary A. H. Goodwin , Fabiano Corsetti , Arash A. Mostofi , Johannes Lischner

The interplay between strong electron-electron interaction and symmetry breaking can have profound influence on the topological properties of materials. In magic angle twisted bilayer graphene (MATBG), the flat band with a single SU(4)…

We derive the exact insulator ground states of the projected Hamiltonian of magic-angle twisted bilayer graphene (TBG) flat bands with Coulomb interactions in various limits, and study the perturbations away from these limits. We define the…

Strongly Correlated Electrons · Physics 2022-04-29 Biao Lian , Zhi-Da Song , Nicolas Regnault , Dmitri K. Efetov , Ali Yazdani , B. Andrei Bernevig

Magic angle twisted trilayer graphene (TTG) has recently emerged as a new platform to engineer strongly correlated flat bands. Here, we reveal the structural and electronic properties of TTG using low temperature scanning tunneling…

In the vicinity of the magic angle in twisted bilayer graphene (TBG), the two low-energy van Hove singularities (VHSs) become exceedingly narrow1-10 and many exotic correlated states, such as superconductivity, ferromagnetism, and…

Strongly Correlated Electrons · Physics 2020-02-25 Yu Zhang , Zhe Hou , Ya-Xin Zhao , Zi-Han Guo , Yi-Wen Liu , Si-Yu Li , Ya-Ning Ren , Qing-Feng Sun , Lin He

Chiral symmetry, fundamental in the physics of graphene, guarantees the existence of topologically stable doubled Dirac cones and anomalous behaviors of the zero-energy Landau level in magnetic fields. The crucial role is inherited in the…

Mesoscale and Nanoscale Physics · Physics 2013-11-13 Y. Hatsugai , T. Morimoto , T. Kawarabayashi , Y. Hamamoto , H. Aoki

Chern insulators are topologically non-trivial states of matter characterized by incompressible bulk and chiral edge states. Incorporating topological Chern bands with strong electronic correlations provides a versatile playground for…

Mesoscale and Nanoscale Physics · Physics 2024-06-14 Qianying Hu , Shu Liang , Xinheng Li , Hao Shi , Xi Dai , Yang Xu

Multilayer moir\'e materials can exhibit topological electronic features yet are inherently quasiperiodic -- leading to wave function interference whose Anderson-localizing tendency can be mitigated by topology. We consider a quasiperiodic…

Mesoscale and Nanoscale Physics · Physics 2025-01-22 Xinghai Zhang , Justin H. Wilson , Matthew S. Foster