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arXiv · 0705.4486

Crossover from weak localization to Shubnikov-de Haas oscillations in a high mobility 2D electron gas

T. A. Sedrakyan·M. E. Raikh
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Abstract

We study the magnetoresistance, δρ_{xx}(B)/ρ_0, of a high-mobility 2D electron gas in the domain of magnetic fields, B, intermediate between the weak localization and the Shubnikov-de Haas oscillations, where δρ_{xx}(B)/ρ_0 is governed by the interaction effects. Assuming short-range impurity scattering, we demonstrate that in the {\em second order} in the interaction parameter, $λ$, a {\em linear} B-dependence, δρ_{xx}(B)/ρ_0\sim λ^2ω_c/E_F with {\em temperature-independent} slope emerges in this domain of B (here ω_c and E_F are the cyclotron frequency and the Fermi energy, respectively). Unlike previous mechanisms, the linear magnetoresistance is {\em unrelated} to the electron executing the full Larmour circle, but rather originates from the impurity scattering via the B-dependence of the {\em phase} of the impurity-induced Friedel oscillations.

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T. A. Sedrakyan, M. E. Raikh. 2008-03-17. Crossover from weak localization to Shubnikov-de Haas oscillations in a high mobility 2D electron gas. https://doi.org/10.1103/physrevlett.100.106806

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