High-temperature quantum anomalous Hall regime in a MnBi2Te4/Bi2Te3superlattice

The quantum anomalous Hall effect(1,2)is a fundamental transport response of a topological insulator in zero magnetic field. Its physical origin is a result of an intrinsically inverted electronic band structure and ferromagnetism(3), and its most important manifestation is the dissipationless flow of chiral charge currents at the edges of the system(4), a property that has the potential to transform future quantum electronics(5,6). Here, we report a Berry-curvature-driven(4,7)anomalous Hall regime at temperatures of several Kelvin in the magnetic topological bulk crystals in which Mn ions self-organize into a period-ordered MnBi2Te4/Bi(2)Te(3)superlattice. Robust ferromagnetism of the MnBi(2)Te(4)monolayers opens a surface gap(8-10), and when the Fermi level is tuned to be within this gap, the anomalous Hall conductance reaches ane(2)/hquantization plateau, which is a clear indication of chiral transport through the edge states. The quantization in this regime is not obstructed by the bulk conduction channels and therefore should be present in a broad family of topological magnets. A three-dimensional topological magnetic superlattice structure exhibits the quantum anomalous Hall effect when the Fermi energy is tuned into the correct energy window.