[{"key":"dc.contributor.author","value":"Patel, Hrishikesh","language":null},{"key":"dc.date.accessioned","value":"2026-04-16T14:03:27Z","language":null},{"key":"dc.date.available","value":"2026-04-16T14:03:29Z","language":null},{"key":"dc.date.issued","value":"2026","language":"en"},{"key":"dc.identifier.uri","value":"http:\/\/hdl.handle.net\/2429\/94108","language":null},{"key":"dc.description.abstract","value":"Recent advances in experimental techniques have helped establish unprecedented control over the electronic structure and properties of 2D materials. Moir\u00e9 materials are created by producing a small lattice mismatch between two superimposed lattices by introducing a small relative twist or superimposing lattices with different lattice constants. Moir\u00e9 graphene structures have been shown to host a variety of interesting phases, like superconductivity and strongly-correlated topological insulators. The quantum devices group at UBC assembled a 5-layer moir\u00e9 graphene structure with a relative twist between a bilayer and a trilayer stack. They measured the Longitudinal and Hall resistivity while varying an out-of-plane electric field (D) through the stack and the electron density (n) in the layers. They showed that in the presence of a non-zero electric field and a small magnetic field, spontaneously symmetry broken correlated topological insulators are obtained at integer fillings with respect to charge neutrality. Many non-trivial metallic phases (halos) have also been observed in the vicinity of the insulators in the D vs. n phase diagram. The goal of this thesis is to gain a theoretical understanding of these insulators and phases surrounding these insulators through a mean field approach. This is achieved by starting with the phenomenological Bistritzer-MacDonald model of t2+3 and adding correlations through a Hartree-Fock decoupling of Coulomb interactions. The nature of the symmetry broken insulators is characterized through Spin-Valley order parameter calculations. In addition, layer polarization and screening in the graphene stack is accounted for self-consistently and discussed in context of the halos.  All results have been contextualized with experimental parameters and assumptions of the theory.","language":"en"},{"key":"dc.language.iso","value":"eng","language":"en"},{"key":"dc.publisher","value":"University of British Columbia","language":"en"},{"key":"dc.rights","value":"Attribution-NonCommercial-NoDerivatives 4.0 International","language":"*"},{"key":"dc.rights.uri","value":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/","language":"*"},{"key":"dc.title","value":"Understanding correlated phases in twisted multilayer graphene","language":"en"},{"key":"dc.type","value":"Text","language":"en"},{"key":"dc.degree.name","value":"Master of Science - MSc","language":"en"},{"key":"dc.degree.discipline","value":"Physics","language":"en"},{"key":"dc.degree.grantor","value":"University of British Columbia","language":"en"},{"key":"dc.contributor.supervisor","value":"Franz, Marcel","language":null},{"key":"dc.date.graduation","value":"2026-05","language":"en"},{"key":"dc.type.text","value":"Thesis\/Dissertation","language":"en"},{"key":"dc.description.affiliation","value":"Science, Faculty of","language":"en"},{"key":"dc.description.affiliation","value":"Physics and Astronomy, Department of","language":"en"},{"key":"dc.degree.campus","value":"UBCV","language":"en"},{"key":"dc.description.scholarlevel","value":"Graduate","language":"en"}]