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Related papers: Integrability in the chiral model of magic angles

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We combine state-of-the-art large-scale first principles calculations with a low-energy continuum model to describe the nearly flat bands of twisted bilayer graphene at the first magic angle $\theta =1.08^\circ$. We show that the energy…

Mesoscale and Nanoscale Physics · Physics 2019-05-22 Procolo Lucignano , Dario Alfè , Vittorio Cataudella , Domenico Ninno , Giovanni Cantele

Theoretical and experimental studies have verified the existence of ``magic angles'' in twisted bilayer graphene, where the twist between layers gives rise to flat bands and consequently highly correlated phases. Narrow bands can also exist…

Strongly Correlated Electrons · Physics 2024-03-20 D. C. W. Foo , Z. Zhan , Mohammed M. Al Ezzi , L. Peng , S. Adam , F. Guinea

The Bistritzer-MacDonald continuum model (BM model) describes the low-energy moir\'e bands for twisted bilayer graphene (TBG) at small twist angles. We derive a generalized continuum model for TBG near any commensurate twist angle, which is…

Mesoscale and Nanoscale Physics · Physics 2022-09-20 Michael G. Scheer , Kaiyuan Gu , Biao Lian

Twisted bilayer graphene develop quasi-flat bands at specific "magic" interlayer rotation angles through an unconventional mechanism connected to carrier chirality. Quasi-flat bands are responsible for a wealth of exotic,…

Mesoscale and Nanoscale Physics · Physics 2020-11-25 María Rosendo , Fernando Peñaranda , Johan Christensen , Pablo San-Jose

Motivated by recent Physical Review Letters of Wang-Liu and Ledwith-Vishwanath-Khalaf, we study Tarnopolsky-Kruchkov-Vishwanath chiral model of two sheets of $n$-layer Bernal stacked graphene twisted by a small angle using the framework…

Mathematical Physics · Physics 2023-11-16 Mengxuan Yang

We study tunneling of charge carriers in single- and bilayer graphene. We propose an explanation for non-zero "magic angles" with 100% transmission for the case of symmetric potential barrier, as well as for their almost-survival for…

Mesoscale and Nanoscale Physics · Physics 2015-10-14 V. Kleptsyn , A. Okunev , I. Schurov , D. Zubov , M. I. Katsnelson

We discuss the full optical response of twisted bilayer graphene at the neutrality point close to the magic angle within the continuum model (CM). Firstly, we identify three different channels consistent with the underlying $D_3$ symmetry,…

Mesoscale and Nanoscale Physics · Physics 2023-09-06 T. Stauber , M. Wackerl , P. Wenk , D. Margetis , J. González , G. Gómez-Santos , J. Schliemann

We consider small random perturbations of the standard high-symmetry tunneling potentials in the Bistritzer-MacDonald Hamiltonian describing twisted bilayer graphene. Using methods developed by Sj\"ostrand for studying the spectral…

Mathematical Physics · Physics 2024-02-21 Simon Becker , Izak Oltman , Martin Vogel

Twisted bilayer graphene exhibits isolated, relatively flat electronic bands near charge neutrality when the interlayer rotation is tuned to specific magic angles. These small misalignments, typically below 1.1{\deg}, result in long-period…

Mesoscale and Nanoscale Physics · Physics 2026-03-26 Antonio Palamara , Michele Pisarra , Antonello Sindona

The study of twisted bilayer graphene (TBG) is a hot topic in condensed matter physics with special focus on {\em magic angles} of twisting at which TBG acquires unusual properties. Mathematically, topologically non-trivial flat bands…

Mesoscale and Nanoscale Physics · Physics 2023-11-03 Maciej Zworski , Mengxuan Yang , Zhongkai Tao

The chiral Hamiltonian for twisted graphene bilayers is analyzed in terms of its squared Hamiltonian which removes the particle-hole symmetry and thus one bipartite lattice, allowing to write the Hamiltonian in terms of a $2\times 2$…

Mesoscale and Nanoscale Physics · Physics 2022-04-13 Leonardo A. Navarro-Labastida , Abdiel Espinosa-Champo , Enrique Aguilar-Mendez , Gerardo G. Naumis

When two monolayers of graphene are stacked with a small relative twist angle, the resulting band structure exhibits a remarkably flat pair of bands at a sequence of 'magic angles' where correlation effects can induce a host of exotic…

Strongly Correlated Electrons · Physics 2019-08-14 Eslam Khalaf , Alex J. Kruchkov , Grigory Tarnopolsky , Ashvin Vishwanath

We investigate the effect of a magnetic field on the band structure of bilayer graphene with a magic twist angle of 1.08{\deg}. The coupling of a tight-binding model and the Peierls phase allows the calculation of the energy bands of…

Mesoscale and Nanoscale Physics · Physics 2024-05-20 Gaëlle Bigeard , Alessandro Cresti

The observation of delicate correlated phases in twisted heterostructures of graphene and transition metal dichalcogenides suggests that moir\'e flat bands are intrinsically resilient against certain types of disorder. Here, we investigate…

Mesoscale and Nanoscale Physics · Physics 2025-07-22 Valentin Crépel , Peize Ding , Nishchhal Verma , Nicolas Regnault , Raquel Queiroz

We introduce a minimum tight-binding model with only three parameters extracted from graphene and untwisted bilayer graphene. This model reproduces quantitatively the electronic structure of not only these two systems and bulk graphite near…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 Xianqing Lin , David Tománek

Twisting bilayer sheets of graphene have been proven to be an efficient way to manipulate the electronic Dirac-like properties, resulting in flat bands at magic angles. Inspired by the electronic model, we develop a continuum model for the…

Materials Science · Physics 2023-09-20 Emmanuele Cappelluti , Jose Angel Silva-Guillén , Habib Rostami , Francisco Guinea

We consider the chiral model of twisted bilayer graphene introduced by Tarnopolsky-Kruchkov-Vishwanath (TKV). TKV have proved that for inverse twist angles $\alpha$ such that the effective Fermi velocity at the moir\'e $K$ point vanishes,…

Mathematical Physics · Physics 2022-08-23 Alexander B. Watson , Mitchell Luskin

Flat band electronic modes are responsible for superconductivity in twisted bilayer graphene (TBG) rotated at magic angles. From there other magic angles can be found for any multilayered twisted graphene systems. Eventually, this lead to…

Mesoscale and Nanoscale Physics · Physics 2022-12-15 Leonardo A. Navarro-Labastida , Gerardo G. Naumis

Graphene bilayers exhibit zero-energy flat bands at a discrete series of magic twist angles. In the absence of intra-sublattice inter-layer hopping, zero-energy states satisfy a Dirac equation with a non-abelian SU(2) gauge potential that…

Mesoscale and Nanoscale Physics · Physics 2021-01-13 Yafei Ren , Qiang Gao , A. H. MacDonald , Qian Niu

We study the effect of an in-plane magnetic field on the non-interacting dispersion of twisted bilayer graphene. Our analysis is rooted in the chirally symmetric continuum model, whose zero-field band structure hosts exactly flat bands and…

Strongly Correlated Electrons · Physics 2020-05-20 Yves H. Kwan , S. A. Parameswaran , S. L. Sondhi