  MnBi2Te4 is an intrinsic magnetic topological insulator where a naturally
occurring band inversion and spontaneous magnetization cooperate to yield
strong, often quantized, anomalous Hall effects. Quasi-three-dimensional
compensated MnBi2Te4 is antiferromagnetic, but undergoes a spin-flop transition
at intermediate fields, resulting in an unusual metastable canted phase before
saturation. In this work, synthesis by molecular beam epitaxy allows us to
obtain a large-area 24-layer antiferromagnetic MnBi2Te4 with near-perfect
compensation that hosts the phase diagram of bulk MnBi2Te4 and a strong
anomalous Hall effect (AHE). This AHE exhibits an antiferromagnetic response at
low magnetic fields, and a clear evolution at intermediate fields through
surface and bulk spin-flop transitions and into saturation. We also show that
the anomalous Hall conductivity is super-linear versus magnetization,
evidencing a non-collinear magnetic texture as magnetization evolves towards
saturation. The strong impact of this non-collinear magnetic structure on the
AHE measured here can be promising for the realization of electronic states
predicted to occur in this magnetic regime of MnBi2Te4.
