We study the disorder dependence of the phase coherence time of quasi one-dimensional wires and two-dimensional (2D) Hall bars fabricated from a high mobility GaAs/AlGaAs heterostructure. Using an original ion implantation technique, we can tune the intrinsic disorder felt by the 2D electron gas and continuously vary the system from the semi-ballistic regime to the localized one. In the diffusive regime, the phase coherence time follows a power law as a function of diffusion coefficient as expected in the Fermi liquid theory, without any sign of low temperature saturation. Surprisingly, in the semi-ballistic regime, it becomes independent of the diffusion coefficient. In the strongly localized regime we find a diverging phase coherence time with decreasing temperature, however, with a smaller exponent compared to the weakly localized regime.
@article{arxiv.0911.3201,
title = {Quantum Coherence at Low Temperatures in Mesoscopic Systems: Effect of Disorder},
author = {Yasuhiro Niimi and Yannick Baines and Thibaut Capron and Dominique Mailly and Fang-Yuh Lo and Andreas D. Wieck and Tristan Meunier and Laurent Saminadayar and Christopher Bauerle},
journal= {arXiv preprint arXiv:0911.3201},
year = {2015}
}