Electric Field Scaling at aB=0Metal-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 $B=0\mathrm{}$. Comparison with the temperature scaling yields separate determinations of the correlation length exponent, $\nu \approx 1.5$, and the dynamical exponent, $z\approx 0.8$, close to the theoretical value $z=1\mathrm{}$.