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High Frequency Conductivity in the Quantum Hall Regime

F. Hohls·U. Zeitler·R. J. Haug
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Abstract

We have measured the complex conductivity $σ_{xx}$ of a two-dimensional electron system in the quantum Hall regime up to frequencies of 6 GHz at electron temperatures below 100 mK. Using both its imaginary and real part we show that $σ_{xx}$ can be scaled to a single function for different frequencies and for all investigated transitions between plateaus in the quantum Hall effect. Additionally, the conductivity in the variable-range hopping regime is used for a direct evaluation of the localization length $ξ$. Even for large filing factor distances $δν$ from the critical point we find $ξ\propto δν^{-γ}$ with a scaling exponent $γ=2.3$.

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F. Hohls, U. Zeitler, R. J. Haug. 2000-11-01. High Frequency Conductivity in the Quantum Hall Regime. https://doi.org/10.1103/physrevlett.86.5124

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