title: Effect of disorder on the quantum coherence in mesoscopic wires.
abstract: We present phase coherence time measurements in quasi-one-dimensional mesoscopic wires made from high mobility two-dimensional electron gas. By implanting gallium ions into a GaAs/AlGaAs heterojunction we are able to vary the diffusion coefficient over 2 orders of magnitude. We show that in the diffusive limit, the decoherence time follows a power law as a function of diffusion coefficient as expected by theory. When the disorder is low enough so that the samples are semiballistic, we observe a new and unexpected regime in which the phase coherence time is independent of disorder. In addition, for all samples the temperature dependence of the phase coherence time follows a power law down to the lowest temperatures without any sign of saturation and this strongly suggests that the frequently observed low temperature saturation is not intrinsic.
authors: Institut Néel, CNRS, B.P. 166, 38042 Grenoble Cedex 09, France.
authors: Y
authors: Y
authors: Niimi
authors: Y
authors: Y
authors: Baines
authors: T
authors: T
authors: Capron
authors: D
authors: D
authors: Mailly
authors: F-Y
authors: FY
authors: Lo
authors: A D
authors: AD
authors: Wieck
authors: T
authors: T
authors: Meunier
authors: L
authors: L
authors: Saminadayar
authors: C
authors: C
authors: Bäuerle