Source data for Figures 1-4 in: Layer-engineered quantum anomalous Hall effect in twisted rhombohedral graphene

Realizing programmable topological states in quantum anomalous Hall (QAH) insulators requires tuning their topological invariant, the Chern number C. Here, we report a QAH platform based on twisted rhombohedral graphene, in which C becomes a programmable and electrically tunable degree of freedom. In twisted monolayer-multilayer (1+n) rhombohedral graphene, we find QAH states with C = n where the layer number n = 3, 4 and 5 directly sets the Chern number. We further demonstrate in-situ electrical control. In a twisted monolayer-trilayer device, the sign of C is switched by electrostatic doping or displacement field. In addition, in twisted Bernal bilayer-rhombohedral tetralayer graphene, we drive a displacement-field-induced topological phase transition between two distinct QAH states with C = 3 and C = 4. Our work establishes a layer‑engineered and electrically tunable platform that could lead to on‑demand engineering of correlated topological states.