English
Related papers

Related papers: All "Magic Angles" Are "Stable" Topological

200 papers

Flat electronic bands can accommodate a plethora of interaction driven quantum phases, since kinetic energy is quenched therein and electronic interactions therefore prevail. Twisted bilayer graphene, near so-called the "magic angles",…

Mesoscale and Nanoscale Physics · Physics 2019-03-27 Bitan Roy , Vladimir Juricic

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

Atomically thin van der Waals materials stacked with an interlayer twist have proven to be an excellent platform towards achieving gate-tunable correlated phenomena linked to the formation of flat electronic bands. In this work we…

Twisted Bilayer graphene (TBG) is known to feature isolated and relatively flat bands near charge neutrality, when tuned to special magic angles. However, different criteria for the magic angle such as the vanishing of Dirac speed, minimal…

Strongly Correlated Electrons · Physics 2019-03-27 Grigory Tarnopolsky , Alex J. Kruchkov , Ashvin Vishwanath

The discovery of correlated states and superconductivity in magic-angle twisted bilayer graphene (MATBG) has established moir\'e quantum matter as a new platform to explore interaction-driven and topological quantum phenomena. Multitudes of…

Magic-angle twisted bilayer graphene (MATBG) exhibits a range of correlated phenomena that originate from strong electron-electron interactions. These interactions make the Fermi surface highly susceptible to reconstruction when $ \pm 1,…

Motivated by recent observation of the quantum spin Hall effect in monolayer germanene and twisted bilayer transition-metal-dichalcogenides (TMDs), we study the topological phases of moir\'e twisted bilayers with time-reversal symmetry and…

Mesoscale and Nanoscale Physics · Physics 2024-05-24 Yi-Ming Wu , Daniel Shaffer , Zhengzhi Wu , Luiz H. Santos

In disordered lattices, itinerant electrons typically undergo Anderson localization due to random phase interference, which suppresses their motion. By contrast, in flat-band systems where electrons are intrinsically localized owing to…

Mesoscale and Nanoscale Physics · Physics 2026-04-28 Zhe Hou , Hailong Li , Qing Yan , Yu-Hang Li , Hua Jiang

We predict topological electron crystals driven by the interplay of interlayer Coulomb attraction and topological miniband physics in bilayer graphene--Mott insulator heterostructures. Charge transfer creates a charge neutral, mass…

Mesoscale and Nanoscale Physics · Physics 2026-04-27 Wangqian Miao , Tianyu Qiao , Xue-Yang Song , Yinghai Xu , Yiwei Chen , Lei Wang , Xi Dai

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

We theoretically study the electronic structure of magic-angle twisted bilayer graphene with disordered moir\'e patterns. By using an extended continuum model incorporating non-uniform lattice distortion, we find that the local density of…

Mesoscale and Nanoscale Physics · Physics 2022-06-29 Naoto Nakatsuji , Mikito Koshino

We propose an effective lattice model for the moir\'e structure of the twisted bilayer dice lattice. In the chiral limit, we find that there are flat bands at the zero-energy level at any twist angle besides the magic ones and these flat…

Mesoscale and Nanoscale Physics · Physics 2024-04-25 Di Ma , Yu-Ge Chen , Yue Yu , Xi Luo

We study the Hofstadter butterfly and Landau levels of the twisted bilayer graphene (TBG). We show that the nontrivial fragile topology of the lowest two bands near the charge neutral point makes their Hofstadter butterfly generically…

Mesoscale and Nanoscale Physics · Physics 2020-08-05 Biao Lian , Fang Xie , B. Andrei Bernevig

In the magic-angle twisted bilayer graphene (MA-TBG), strong electron-electron (e-e) correlations caused by the band-flattening lead to many exotic quantum phases such as superconductivity, correlated insulator, ferromagnetism, and quantum…

Materials Science · Physics 2020-05-29 Ya-Ning Ren , Chen Lu , Yu Zhang , Si-Yu Li , Yi-Wen Liu , Chao Yan , Zi-Han Guo , Cheng-Cheng Liu , Fan Yang , Lin He

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

We present a systematic study of the low-energy collective modes for different insulating states at integer fillings in twisted bilayer graphene. In particular, we provide a simple counting rule for the total number of soft modes, and…

Strongly Correlated Electrons · Physics 2020-10-28 Eslam Khalaf , Nick Bultinck , Ashvin Vishwanath , Michael P. Zaletel

The moir\'e of twisted graphene bilayers can generate flat bands in which charge carriers do not posses enough kinetic energy to escape Coulomb interactions with each other leading to the formation of novel strongly correlated electronic…

Mesoscale and Nanoscale Physics · Physics 2021-09-22 F. Mesple , A. Missaoui , T. Cea , L. Huder , G. Trambly de Laissardière , F. Guinea , C. Chapelier , V. T. Renard

In recent years, flat electronic bands in twisted bilayer graphene (TBG) have attracted significant attention due to their intriguing topological properties, extremely slow electron velocities, and enhanced density of states. Extending…

Quantum Gases · Physics 2025-06-16 Wenjie Sui , Wei Han , Zheng Vitto Han , Zengming Meng , Jing Zhang

Bilayer graphene twisted at the angle of about 1.1{\deg} better known as magic angle, exhibits ultra-flat moir\'e superlattice bands that are a source of highly-tunable, exotic quantum phenomena. Such phenomena, like superconductivity,…

Strongly Correlated Electrons · Physics 2024-11-05 Giovanna Feraco , Wissem Boubaker , Petra Rudolf , Antonija Grubišić-Čabo

Graphene moire superlattices have emerged as a platform hosting and abundance of correlated insulating, topological, and superconducting phases. While the origins of strong correlations and non-trivial topology are shown to be directly…