Exclusion of quantum coherence as the origin of the 2D metallic state in high-mobility silicon inversion layers - art. no. 096802

The temperature and density dependence of the phase coherence time tau (phi ) in high-mobility silicon inversion layers was determined from the magneto resistivity due to weak localization. The upper temperature limit for singl e-electron quantum interference effects was delineated by comparing tau (ph i) with the momentum relaxation time tau. A comparison between the density dependence of the borders for quantum interference effects and the strong r esistivity drop reveals that these effects are not related to each other. A s the strong resistivity drop occurs in the Drude regime, the apparent meta llic behavior cannot be caused by quantum coherent effects.