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arXiv · 0904.2438

Optical Hall conductivity in ordinary and graphene QHE systems

Takahiro Morimoto·Yasuhiro Hatsugai·Hideo Aoki
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Abstract

We have revealed from a numerical study that the optical Hall conductivity $σ_{xy}(ω)$ has a characteristic feature even in the ac ($\sim$ THz) regime in that the Hall plateaus are retained both in the ordinary two-dimensional electron gas and in graphene in the quantum Hall (QHE) regime, although the plateau height is no longer quantized in ac. In graphene $σ_{xy}(ω)$ reflects the unusual Landau level structure. The effect remains unexpectedly robust against a 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 $α$.

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Takahiro Morimoto, Yasuhiro Hatsugai, Hideo Aoki. 2009-09-16. Optical Hall conductivity in ordinary and graphene QHE systems. https://doi.org/10.1103/physrevlett.103.116803

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