Topological flat bands and correlated states in twisted monolayer-bilayer graphene

Article Article scientifique Article Topological flat bands and correlated states in twisted monolayer-bilayer graphene eng 2020-07-27 2020-07-27 author Rademaker Louk 0000-0001-6053-8150 906528 author Protopopov Ivan 855348 author Abanin Dmitry 842597 033150 10.1103/PhysRevResearch.2.033150 2643-1564 https://link.aps.org/doi/10.1103/PhysRevResearch.2.033150 Monolayer graphene placed with a twist on top of AB-stacked bilayer graphene hosts topological flat bands in a wide range of twist angles. The dispersion of these bands and gaps between them can be efficiently controlled by a perpendicular electric field, which induces topological transitions accompanied by changes of the Chern numbers. In the regime where the applied electric field induces gaps between the flat bands, we find a relatively uniform distribution of the Berry curvature. Consequently, interaction-induced valley- and/or spin-polarized states at integer filling factors are energetically favorable. In particular, we predict a quantum anomalous Hall state at filling factors ν = 1, 3 for a range of twist angles 1◦ < θ < 1.4◦. Furthermore, to characterize the response of the system to magnetic field, we computed the Hofstadter butterfly and the Wannier plot, which can be used to probe the dispersion and topology of the flat bands in this material. Dewey 500.2 37 Département de physique théorique 133 false 1403 Groupe Rademaker Physical review research 2 3 eecb96bd-d817-4079-afda-5c3a568a31c0 Article (Published version) Public Article-scientifique-from-crossref.pdf 2030013 application/pdf openAccess Faculté des sciences / Section de physique / Département de physique théorique

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Topological flat bands and correlated states in twisted monolayer-bilayer graphene	Physical review research			2020	270	146

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Protopopov, Ivan