Abstract
We reveal from numerical study that the optical Hall conductivity has a characteristic feature even in the ac () regime in that the Hall plateaus are retained both in the ordinary two-dimensional electron gas and in graphene in the quantum Hall regime, although the plateau height is no longer quantized in ac. In graphene reflects the unusual Landau level structure. The effect remains unexpectantly robust against the significant strength of disorder, which we attribute to an effect of localization. We predict the ac quantum Hall measurements are feasible through the Faraday rotation characterized by the fine-structure constant .
- Received 16 April 2009
DOI:https://doi.org/10.1103/PhysRevLett.103.116803
©2009 American Physical Society