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Universal flow diagram for the magnetoconductance in disordered GaAs layers

S. S. Murzin·M. Weiss·A. G. M. Jansen·K. Eberl
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Abstract

The temperature driven flow lines of the diagonal and Hall magnetoconductance data (G_{xx},G_{xy}) are studied in heavily Si-doped, disordered GaAs layers with different thicknesses. The flow lines are quantitatively well described by a recent universal scaling theory developed for the case of duality symmetry. The separatrix G_{xy}=1 (in units e^2/h) separates an insulating state from a spin-degenerate quantum Hall effect (QHE) state. The merging into the insulator or the QHE state at low temperatures happens along a semicircle separatrix G_{xx}^2+(G_{xy}-1)^2=1 which is divided by an unstable fixed point at (G_{xx},G_{xy})=(1,1).

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S. S. Murzin, M. Weiss, A. G. M. Jansen, K. Eberl. 2002-04-09. Universal flow diagram for the magnetoconductance in disordered GaAs layers. https://doi.org/10.1103/physrevb.66.233314

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