Related papers: A primer on Twistronics: Massless Dirac Fermion's journey to Moir\'e patterns and Flat bands in Twisted Bilayer Graphene

A primer on Twistronics: Massless Dirac Fermion's journey to Moir\'e patterns and Flat bands in Twisted Bilayer Graphene

URL: http://arxiv.org/abs/2212.04801v1
Date: Fri, 9 Dec 2022 12:09:46 GMT
Title: A primer on Twistronics: Massless Dirac Fermion's journey to Moir\'e patterns and Flat bands in Twisted Bilayer Graphene
Authors: Deepanshu Aggarwal, Rohit Narula, and Sankalpa Ghosh ( Dept. of Physics, IIT Delhi)
Abstract summary: Recent discovery of strongly correlated phases in magic angle twisted bilayer graphene heralded a new area of investigation into the strongly-correlation physics in graphene. This review article provides a self-contained theoretical perspective of the journey of the wonder material graphene from its single-particle physics dominated regime to the flat band regime of strong-correlation physics.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: The recent discovery of the strongly correlated phases in magic angle twisted bilayer graphene heralded a new area of investigation into the strongly-correlation physics in graphene. This is remarkably different from the initial period of graphene research which was dominated by interest in one body physics of massless Dirac fermions. This pedagogical review article provides a self-contained theoretical perspective of the journey of the wonder material graphene from its single-particle physics dominated regime to the flat band regime of strong-correlation physics. Starting from the origin of Dirac points in condensed matter systems, along this road, this review discusses the effect of superlattice on the Fermi velocity and Van Hove singularities in the dispersion relation of the graphene, and how it naturally leads to investigation into Moir\'e pattern in Van der Wall's heterostructure such as graphene-hexagonal boron-nitride and twisted bilayer graphene. Subsequently It discusses in detail the origin of flat bands in twisted bilayer graphene at the magic angles. by analysing in detail a number of prominent theoretical works in this direction. The theoretical description is intercepted at appropriate places by connecting it with the relevant experimental works. In a final section we also provide a list of the topics in the field of twisted bilayer graphene that are not covered in this review, but can be approached with the help of this primer.

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