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Resistance noise scaling in a 2D system in GaAs

R. Leturcq·G. Deville·D. L'Hote·R. Tourbot·C. J. Mellor·M. Henini
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Abstract

The 1/f resistance noise of a two-dimensional (2D) hole system in a high mobility GaAs quantum well has been measured on both sides of the 2D metal-insulator transition (MIT) at zero magnetic field (B=0), and deep in the insulating regime. The two measurement methods used are described: I or V fixed, and measurement of resp. V or I fluctuations. The normalized noise magnitude SR/R^2 increases strongly when the hole density is decreased, and its temperature (T) dependence goes from a slight increase with T at the largest densities, to a strong decrease at low density. We find that the noise magnitude scales with the resistance, SR /R^2 ~ R^2.4. Such a scaling is expected for a second order phase transition or a percolation transition. The possible presence of such a transition is investigated by studying the dependence of the conductivity as a function of the density. This dependence is consistent with a critical behavior close to a critical density p* lower than the usual MIT critical density pc.

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R. Leturcq, G. Deville, D. L'Hote, R. Tourbot, C. J. Mellor, M. Henini. 2004-12-03. Resistance noise scaling in a 2D system in GaAs. https://doi.org/10.1117/12.546505

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