Optical Observation of the Quantum Hall Effect(Current Topics)

Abstract

In the physics of quantum Hall effect, static (DC) conductions are usually studied. Recently Morimoto, et al. has proposed that when we shine a terahertz light to the sample we should have an "optical Hall effect", a novel concept, where the optical Hall response retains, surprisingly, step-like structures arising from localization physics in AC. The effect is predicted to be observable as a Faraday rotation of polarized lights with the relevant photon energy in THz regime. The effect has subsequently been experimentally observed by Ikebe, et al. with terahertz Faraday rotation for a two-dimensional electron system in GaAs/AlGaAs. We give a brief review both theoretically and experimentally.