Compared with electronic phase transitions, structural phase transitions of crystals are
challenging to control owing to the energy cost of breaking dense solid bonds. Recently …

Rhombohedral-stacked multilayer graphene hosts a pair of flat bands touching at zero
energy, which should give rise to correlated electron phenomena that can be tuned further …

Ferroic orders describe spontaneous polarization of spin, charge and lattice degrees of
freedom in materials. Materials exhibiting multiple ferroic orders, known as multiferroics …

The quantum anomalous Hall effect (QAHE) is a robust topological phenomenon that
features quantized Hall resistance at zero magnetic field. We report the QAHE in a …

We study a model of electrons moving in a parent band of uniform Berry curvature. At
sufficiently high parent Berry curvature, we show that strong repulsive interactions …

Electron valley, a degree of freedom that is analogous to spin, can lead to novel topological
phases in bilayer graphene. A tunable bandgap can be induced in bilayer graphene by an …

We study the electronic structures and topological properties of (M+ N)-layer twisted
graphene systems. We consider the generic situation that N-layer graphene is placed on top …

Degeneracies in multilayer graphene, including spin, valley, and layer degrees of freedom,
can be lifted by Coulomb interactions, resulting in rich broken-symmetry states. Here, we …

A striking feature of bilayer graphene is the induction of a significant band gap in the
electronic states by the application of a perpendicular electric field,,,,,,. Thicker graphene …

The electronic properties of van der Waals (vdW) structures can be substantially modified by
the moiré superlattice potential, which strongly depends on the twist angle among the …