Edge magnetoplasmons in the fractional-quantum-Hall-effect regime

Abstract

We report the observation of resonant edge excitations of a high-mobility two-dimensional electron system in the regime of the fractional quantum Hall effect. Narrow edge resonances are observed only on fractional or integer Hall plateaus and have a resonance frequency proportional to the quantized Hall conductivity. We interpret our results using a new theory of edge magnetoplasmons in the quantum Hall regime.