Scaling behavior of the insulator-to-plateau transition in a topological band model

Scaling behavior of the quantum phase transition from an insulator to a quantum Hall plateau state has often been examined within systems realizing Landau levels. We study the topological transition in an energy-band model with nonzero Chern number, which has the same topological property as a Landau level. We find that a topological band generally realizes the same universality class as the integer quantum Hall system under uniform magnetic flux for strong enough disorder scattering. Furthermore, the symmetry of the transition characterized by relations σxy (E) = 1 − σxy (−E) for Hall conductance and σT (E) = σT (−E) for longitudinal Thouless conductance is observed near the transition region. We also establish that the finite-temperature dependence of Hall conductance is determined by inelastic-scattering relaxation time, while the localization exponent ν remains unchanged by such scattering.