Mesoscopic Behavior Near a Two-Dimensional Metal-Insulator Transition

Abstract

We study conductance fluctuations in a two-dimensional electron gas as a function of chemical potential (or gate voltage) from the strongly insulating to the metallic regime. Power spectra of the fluctuations decay with two distinct exponents (1/v_l and 1/v_h). For conductivity $\sigma \sim 0.1e^2/h$, we find a third exponent (1/v_i) in the shortest samples, and non-monotonic dependence of v_i and v_l on σ. We study the dependence of v_i, v_l, v_h, and the variances of corresponding fluctuations on σ, sample size, and temperature. The anomalies near $\sigma \simeq 0.1e^2/h$ indicate that the dielectric response and screening length are critically behaved, i.e. that Coulomb correlations dominate the physics.

Revised according to referee remarks

References in corpus (3)

• Electric field scaling at a B=0 metal-insulator transition in two dimensions
• Scaling theory of two-dimensional metal-insulator transitions
• Re-entrant resonant tunneling

Cited by in corpus (5)

• Onset of Glassy Dynamics in a Two-Dimensional Electron System in Silicon
• Critical spectral statistics in two-dimensional interacting disordered systems
• Localized to extended states transition for two interacting particles in a two-dimensional random potential
• Metal-Insulator Transition in a Low-Mobility Two-Dimensional Electron System
• Conductance Fluctuations Near the Two-Dimensional Metal-Insulator Transition