Gate-Tunable Fractional Chern Insulators in Twisted Double Bilayer Graphene

Zhao Liu, Ahmed Abouelkomsan, and Emil J. Bergholtz

We predict twisted double bilayer graphene to be a versatile platform for the realization of fractional Chern insulators readily targeted by tuning the gate potential and the twist angle. Remarkably, these topologically ordered states of matter, including spin singlet Halperin states and spin polarized states in Chern number $C=1$ and $C=2$ bands, occur at high temperatures and without the need for an external magnetic field.

Phys. Rev. Lett. 126, 026801

The published article is available at https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.126.026801