A Unified Picture Of The Scaling And Non-Scaling Behavior In Quantum Hall Plateau Transitions

Abstract

A unified picture of the scaling and non‐scaling behavior in quantum Hall plateau transitions is proposed. We show that the interband mixing of states with opposite chiralities and the degrees of the inter‐Landau‐band overlap are the key ingredients to the problem. We find that the mixing of states with opposite chiralities tends to delocalize electronic states, leading to the formation of extended‐state band near the center of each Landau subband. However, this requires sufficient interband overlap to interlock the two sets of states. We find extended states in each Landau band evolve from its center to a narrow band around the center as the interband overlap increases. Thus the nature of a plateau transition changes from a continuous phase transition at a low interband overlap to a cross of a narrow metallic phase at a high interband overlap.