Figure 4: Global phase diagram of quantum anomalous Hall effect.
From: Metal-to-insulator switching in quantum anomalous Hall states
(a) Angle-assisted QAHE phase transition in the (σxx, σxy) plot. The six QL Cr-doped TI film is continuously rotated from 90°(out-of-plane) to 180° (in-plane) with respect to the applied magnetic field direction. All curves overlap with each other following the single semicircle relation. Data are shifted vertically by (B−1) × 0.1e2/h for convenient comparison. (b,c) Magnetic field-dependent QAHE phase diagram in the three-dimensional plot. When B//<1 T, the semicircle transition cannot be completed. (d) Comparison between the field-dependent Rxx–Rxy results (with the sweeping direction of the applied magnetic field from +0.3 T to −0.3 T) and the angle-dependent data in a (θ⊆[90°, 270°] and B=1 T). Identical QAHE phase transition between the C1=0 insulating state and the two C1=± 1 QAHE states is manifested. (e) Temperature-dependent (σxx, σxy) plot. As T increases, the intrinsic localization scaling rule diverts the system from the original QAHE and insulating states. The dotted lines link the data points with the same angles (θ⊆[90°, 270°] with each step of 10°) between 0.02 and 1.9 K.
