Weak-coupling theory of magic-angle twisted bilayer graphene
Strong correlations occur in magic-angle twisted bilayer graphene (MATBG) when the octet of flat moiré minibands centered on charge neutrality (CN) is partially occupied. The octet consists of a single valence band and a single conduction band for each of four degenerate spin-valley flavors. Motivat...
| Authors: | , , , |
|---|---|
| Format: | article |
| Publication Date: | 2024 |
| Country: | España |
| Institution: | Universitat Politècnica de Catalunya (UPC) |
| Repository: | UPCommons. Portal del coneixement obert de la UPC |
| Language: | English |
| OAI Identifier: | oai:upcommons.upc.edu:2117/427275 |
| Online Access: | https://hdl.handle.net/2117/427275 https://dx.doi.org/10.1103/PhysRevB.110.L121117 |
| Access Level: | Open access |
| Keyword: | Gravitational waves Graphene Energy-band theory of solids Electronic structure Ones gravitacionals Grafè Banda d'energia (Física) Estructura electrònica Àrees temàtiques de la UPC::Física::Relativitat |
| Summary: | Strong correlations occur in magic-angle twisted bilayer graphene (MATBG) when the octet of flat moiré minibands centered on charge neutrality (CN) is partially occupied. The octet consists of a single valence band and a single conduction band for each of four degenerate spin-valley flavors. Motivated by the importance of Hartree electrostatic interactions in determining the filling-factor-dependent band structure, we use a time-dependent Hartree approximation to gain insight into electronic correlations. We find that the electronic compressibility is dominated by Hartree interactions, that paramagnetic states are stable over a range of density near CN, and that the dependence of energy on flavor polarization is strongly overestimated by mean-field theory. |
|---|