Dephasing and the metal-insulator transition - art. no. 045123

The metal-insulator transition (MTT) observed in two-dimensional (2D) syste ms is apparently contradictory to the well-known scaling theory of localiza tion. By investigating the conductance of disordered one-dimensional system s with a finite phase coherence length, we show that by changing the phase- coherence length or the localization length, it is possible to observe the transition from insulator-like behavior to metal-like behavior, and the tra nsition is a crossover between the quantum and classical regimes. The resem blance between our calculated results and the experimental findings of 2D M IT suggests that the observed metallic phase could be the result of a finit e dephasing rate.