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Measurements of Composite Fermion Conductivity Dependence on Carrier Density

C. -T. Liang·M. Y. Simmons·D. A. Ritchie·M. Pepper
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Abstract

We present the first experimental study of the carrier density dependence of the composite fermion conductivity $σ^{CF}_{xx}$ at Landau level filling factors $ν= {1/2}$ and $ν= {3/2}$ in high-quality front-gated GaAs/Al$_{0.33}$Ga$_{0.67}$As heterostructures. Extracting $α$ from the power law ln$(σ^{CF}_{xx}) \propto$ ln$(n_e)^α$ shows that $α\approx 1$. The measured $α \approx 1$ is placed between the predicted value 3/4 in the strong random magnetic field regime, and 3/2 in the weak random magnetic field regime. Comparisons between our results and theory are discussed.

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C. -T. Liang, M. Y. Simmons, D. A. Ritchie, M. Pepper. 2005-03-17. Measurements of Composite Fermion Conductivity Dependence on Carrier Density. https://doi.org/10.1088/0953-8984%2F16%2F7%2F009

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