Europhys. Lett., 61 (5) , pp. 674-680 (2003)
Transport signatures of correlated disorder in a two-dimensional electron gasT. Heinzel1, R. Jäggi1, E. Ribeiro1, M. v. Waldkirch1, K. Ensslin1, S. E. Ulloa1, 2, G. Medeiros-Ribeiro3 and P. M. Petroff3
1 Solid State Physics Laboratory, ETH Zürich - 8093 Zürich, Switzerland
2 Department of Physics and Astronomy, Ohio University Athens, OH 45701-2979, USA
3 Materials Department, University of California - Santa Barbara, CA 93106, USA
(Received 14 May 2002; accepted in final form 19 December 2002)
We report electronic transport measurements on two-dimensional electron gases in a heterostructure with an embedded layer of self-assembled quantum dots. At high dot densities, pronounced Altshuler-Aronov-Spivak magnetoresistance oscillations are observed, which indicate short-range ordering of the potential landscape formed by the charged dots and the strain fields. The presence of these oscillations coincides with the observation of a metal-insulator transition, and a maximum in the electron mobility as a function of the electron density. Within a model based on correlated disorder, we establish a relation between these effects.
73.40.-c - Electronic transport in interface structures.
73.21.La - Quantum dots.
72.15.Rn - Localization effects (Anderson or weak localization).
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