Whitney Mason

Electric Field Scaling at a B=0 Metal-Insulator Transition in Two Dimensions.

The nonlinear (electric field-dependent) resistivity of the 2D electron system in silicon exhibits scaling as a function of electric field and electron density in both the metallic and insulating phases, providing further evidence for a true metal-insulator transition in this 2D system at {ital B}=0. Comparison with the temperature scaling yields separate determinations of the correlation length exponent, {nu}{approx_equal}1.5, and the dynamical exponent, {ital z}{approx_equal}0.8, close to the theoretical value {ital z}=1. {copyright} {ital 1996 The American Physical Society.}

Electric Field Scaling at a {ital B={bold 0}} Metal-Insulator Transition in Two Dimensions

The nonlinear (electric field-dependent) resistivity of the 2D electron system in silicon exhibits scaling as a function of electric field and electron density in both the metallic and insulating phases, providing further evidence for a true metal-insulator transition in this 2D system at {ital B}=0. Comparison with the temperature scaling yields separate determinations of the correlation length exponent, {nu}{approx_equal}1.5, and the dynamical exponent, {ital z}{approx_equal}0.8, close to the theoretical value {ital z}=1. {copyright} {ital 1996 The American Physical Society.}

Experimental evidence for a Coulomb gap in two dimensions.

We have studied the resistivity,

Experimental evidence of the Coulomb gap in a high-mobility 2D electron system in silicon

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Scaling of a metal/insulator transition in a 2D system at B = 0

, of a two-dimensional electron system in silicon in the temperature range 200 mK < T < 7.5 K at zero magnetic field at low electron densities, when the electron system is in the insulating regime. Our results show that at an intermediate temperature range

Destruction of the quantum Hall effect with increasing disorder.

\rho=\rho_0 exp[(T_0/T)^{1/2}]

Temperature induced insulator-metal-QHE transitions

for at least four orders of magnitude up to 3x10^9 Ohms. This behavior is consistent with the existence of a Coulomb gap. Near the metal/insulator transition, the prefactor was found to be close to

Temperature-induced transitions between insulator, metal, and quantum Hall states in a two-dimensional electron system

h/e^2

Scaling of an anomalous metal-insulator transition in a two-dimensional system in silicon at B=0.

, and resistivity scales with temperature. For very low electron densities,

Global phase diagram for the quantum Hall effect: An experimental picture.

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