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

We study the magnetoresistance xx(B)/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 xx(B)/0 is governed by the interaction effects. Assuming short-range impurity scattering, we demonstrate that in the second order in the interaction parameter λ a linear B dependence, xx(B)/ 02 I c/EF with a temperature-independent slope, emerges in this domain of B (here ωc and EF are the cyclotron frequency and the Fermi energy, respectively). Unlike previous mechanisms, the linear magnetoresistance is unrelated to the electron executing the full Larmour circle, but rather originates from the impurity scattering via the B dependence of the phase of the impurity-induced Friedel oscillations.