Universal Scaling of Quantum Anomalous Hall Plateau Transition

We study the critical properties of the quantum anomalous Hall (QAH) plateau transition in magnetic topological insulators. We introduce a microscopic model for the plateau transition in QAH effect at the coercive field and then map it to the network model of quantum percolation in the integer quantum Hall effect plateau transition. Generally, an intermediate plateau with zero Hall conductance could occur at the coercive field. $\sigma_{xx}$ would have double peaks at the coercivity while $\rho_{xx}$ only has single peak. Remarkably, this theoretical prediction is already borne out in experiment. Universal scaling of the transport coefficients $\rho_{xy}$ and $\rho_{xx}$ are predicted.