• Corpus ID: 244773557

Charge order and antiferromagnetism in twisted bilayer graphene from the variational cluster approximation

  title={Charge order and antiferromagnetism in twisted bilayer graphene from the variational cluster approximation},
  author={Bahareh Pahlevanzadeh and Peyman Sahebsara and David S'en'echal},
Abstract We study the possibility of charge order at quarter filling and antiferromagnetism at halffilling in a tight-binding model of magic angle twisted bilayer graphene. We build on the model proposed by Kang and Vafek [1], relevant to a twist angle of 1.30◦, and add on-site and extended density-density interactions. Applying the variational cluster approximation with an exact-diagonalization impurity solver, we find that the system is indeed a correlated (Mott) insulator at fillings 4 , 1 2… 

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