Abstract
We identify states favored by Coulomb interactions projected onto the Wannier basis of the four narrow bands of the “magic angle” twisted bilayer graphene. At the filling of 2 electrons/holes per moiré unit cell, such interactions favor an insulating ferromagnet. The kinetic terms select the ground state in which the two valleys with opposite spins are equally mixed, with a vanishing magnetic moment per particle. We also find extended excited states, the gap to which decreases in the magnetic field. An insulating stripe ferromagnetic phase is favored at 1 electron/hole per unit cell.
- Received 4 November 2018
DOI:https://doi.org/10.1103/PhysRevLett.122.246401
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