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Resistance Noise Scaling in a Dilute Two-Dimensional Hole System in GaAs

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

We have measured the resistance noise of a two-dimensional (2D)hole system in a high mobility GaAs quantum well, around the 2D metal-insulator transition (MIT) at zero magnetic field. The normalized noise power $S_R/R^2$ increases strongly when the hole density p_s is decreased, increases slightly with temperature (T) at the largest densities, and decreases strongly with T at low p_s. The noise scales with the resistance, $S_R/R^2 \sim R^{2.4}$, as for a second order phase transition such as a percolation transition. The p_s dependence of the conductivity is consistent with a critical behavior for such a transition, near a density p* which is lower than the observed MIT critical density p_c.

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R. Leturcq, D. L'Hote, R. Tourbot, C. J. Mellor, M. Henini. 2003-02-13. Resistance Noise Scaling in a Dilute Two-Dimensional Hole System in GaAs. https://doi.org/10.1103/physrevlett.90.076402

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