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Conductance Fluctuations Near the Two-Dimensional Metal-Insulator Transition

K. P. Li·Dragana Popovic·S. Washburn
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Abstract

Measurements of conductance $G$ on short, wide, high-mobility Si-MOSFETs reveal both a two-dimensional metal-insulator transition (MIT) at moderate temperatures (1 $<~ T <$ 4~K) and mesoscopic fluctuations of the conductance at low temperatures ($T~ <$ 1~K). Both were studied as a function of chemical potential (carrier concentration $n_s$) controlled by gate voltage ($V_g$) and magnetic field $B$ near the MIT. Fourier analysis of the low temperature fluctuations reveals several fluctuation scales in $V_g$ that vary non-monotonically near the MIT. At higher temperatures, $G(V_g,B)$ is similar to large FETs and exhibits a MIT. All of the observations support the suggestion that the MIT is driven by Coulomb interactions among the carriers.

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K. P. Li, Dragana Popovic, S. Washburn. 1997-08-21. Conductance Fluctuations Near the Two-Dimensional Metal-Insulator Transition. https://doi.org/10.1016/s0921-4526(98)00174-4

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