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Related papers: Correlated Insulators in Twisted Bilayer Graphene

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This is a theoretical study of electron transport in gated bilayer graphene - a novel semiconducting material with a tunable band gap. It is shown that the which-layer pseudospin coherence enhances the subgap conductivity and facilitates…

Mesoscale and Nanoscale Physics · Physics 2012-05-28 Maxim Trushin

Magic-angle twisted bilayer graphene has recently become a thriving material platform realizing correlated electron phenomena taking place within its topological flat bands. Several numerical and analytical methods have been applied to…

Strongly Correlated Electrons · Physics 2021-09-17 Bin-Bin Chen , Yuan Da Liao , Ziyu Chen , Oskar Vafek , Jian Kang , Wei Li , Zi Yang Meng

Interplay of strong correlation and flat topological band has been a central problem in moir\'e systems such as the magic angle twisted bilayer graphene (TBG). Recent studies show that Mott-like states may still be possible in TBG despite…

Strongly Correlated Electrons · Physics 2025-07-02 Jing-Yu Zhao , Boran Zhou , Ya-Hui Zhang

The emergence of flat bands and correlated behaviors in 'magic angle' twisted bilayer graphene (tBLG) has sparked tremendous interest, though many aspects of the system are under intense debate. Here we report observation of both…

We consider bilayer graphene in the presence of spin orbit coupling, to assess its behavior as a topological insulator. The first Chern number $n$ for the energy bands of single and bilayer graphene is computed and compared. It is shown…

Mesoscale and Nanoscale Physics · Physics 2011-07-18 E. Prada , P. San-Jose , L. Brey , H. A. Fertig

Correlated insulators are frequently observed in magic angle twisted bilayer graphene at even fillings of electrons or holes per moir\'e unit-cell. Whereas theory predicts these insulators to be intervalley coherent excitonic phases, the…

Mesoscale and Nanoscale Physics · Physics 2023-02-15 Gal Shavit , Kryštof Kolář , Christophe Mora , Felix von Oppen , Yuval Oreg

Although much progress has been made on the physics of magic angle twisted bilayer graphene at integer fillings, little attention has been given to fractional fillings. Here we show that the three-peak structure of Wannier orbitals,…

Mesoscale and Nanoscale Physics · Physics 2021-05-31 Kevin Zhang , Yang Zhang , Liang Fu , Eun-Ah Kim

The discovery of different phases as a result of correlations, especially in low-dimensional materials, has been always an exciting and fundamental subject of research. Recent experiments on twisted bilayer graphene have revealed reentrant…

Strongly Correlated Electrons · Physics 2018-11-30 Yury Sherkunov , Joseph J. Betouras

Pristine bilayer graphene behaves in some instances as an insulator with a transport gap of a few meV. This behaviour has been interpreted as the result of an intrinsic electronic instability induced by many-body correlations. Intriguingly,…

Mesoscale and Nanoscale Physics · Physics 2014-04-29 P. San-Jose , R. V. Gorbachev , A. K. Geim , K. S. Novoselov , F. Guinea

The electronic dispersion of a graphene bilayer is highly dependent on rotational mismatch between layers and can be further manipulated by electrical gating. This allows for an unprecedented control over electronic properties and opens up…

Materials Science · Physics 2016-08-31 Johannes C. Rode , Dmitri Smirnov , Hennrik Schmidt , Rolf J. Haug

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

Twisted bilayer graphene (TBG) provides a unique framework to elucidate the interplay between strong correlations and topological phenomena in two-dimensional systems. The existence of multiple electronic degrees of freedom -- charge, spin,…

Strongly Correlated Electrons · Physics 2021-01-27 Yuan Da Liao , Jian Kang , Clara N. Breiø , Xiao Yan Xu , Han-Qing Wu , Brian M. Andersen , Rafael M. Fernandes , Zi Yang Meng

Twisted bilayer graphene with a twist angle of around 1.1{\deg} features a pair of isolated flat electronic bands and forms a strongly correlated electronic platform. Here, we use scanning tunneling microscopy to probe local properties of…

We devise a model to explain why twisted bi-layer graphene (TBLG) exhibits insulating behavior when $\nu=2,3$ charges occupy a unit moir\'e cell, a feature attributed to Mottness, but not for $\nu=1$, clearly inconsistent with Mott…

Strongly Correlated Electrons · Physics 2018-10-15 Bikash Padhi , Chandan Setty , Philip W. Phillips

Twisted bilayer graphene (TBG) is remarkable for its topological flat bands, which drive strongly-interacting physics at integer fillings, and its simple theoretical description facilitated by the Bistritzer-MacDonald Hamiltonian, a…

Strongly Correlated Electrons · Physics 2022-08-10 Jonah Herzog-Arbeitman , Aaron Chew , Dmitri K. Efetov , B. Andrei Bernevig

The folding of monolayer graphene leads to new layered systems, termed twisted bilayer graphene (TBG), generally displaying a certain interlayer rotation away from crystallographic alignment. We here present an atomic force microscopy study…

Materials Science · Physics 2016-08-30 Johannes C. Rode , Christopher Belke , Hennrik Schmidt , Rolf J. Haug

We present a simple model that we believe captures the key aspects of the competition between superconducting and insulating states in twisted bilayer graphene. Within this model, the superconducting phase is primary, and arises at generic…

Strongly Correlated Electrons · Physics 2019-09-16 Yang-Zhi Chou , Yu-Ping Lin , Sankar Das Sarma , Rahul M. Nandkishore

We identify states favored by Coulomb interactions projected onto the Wannier basis of the four narrow bands of the "magic angle" twisted bilayer graphene. At the filling of two electrons/holes per moire unit cell, such interactions favor…

Strongly Correlated Electrons · Physics 2019-06-20 Jian Kang , Oskar Vafek

Bilayer graphene twisted by a small angle shows a significant charge modulation away from neutrality, as the charge in the narrow bands near the Dirac point is mostly localized in the regions of the Moir\'e pattern with $AA$ stacking. The…

Mesoscale and Nanoscale Physics · Physics 2018-12-13 Francisco Guinea , Niels R. Walet

Electronic correlations in two-dimensional materials play a crucial role in stabilising emergent phases of matter. The realisation of correlation-driven phenomena in graphene has remained a longstanding goal, primarily due to the absence of…

Mesoscale and Nanoscale Physics · Physics 2023-09-19 Saisab Bhowmik , Arindam Ghosh , U. Chandni