  Theory of weak localization in two-dimensional high-mobility semiconductor
systems is developed with allowance for the spin-orbit interaction. The
obtained expressions for anomalous magnetoresistance are valid in the whole
range of classically weak magnetic fields and for arbitrary strengths of bulk
and structural inversion asymmetry contributions to the spin splitting. The
theory serves for both diffusive and ballistic regimes of electron propagation
taking into account coherent backscattering and nonbackscattering processes.
The transition between weak localization and antilocalization regimes is
analyzed. The manifestation of the mutual compensation of Rashba and
Dresselhaus spin splittings in magnetoresistance is discussed. Perfect
description of experimental data on anomalous magnetoresistance in
high-mobility heterostructures is demonstrated. The in-plane magnetic field
dependence of the conductivity caused by an interplay of the spin-orbit
splittings and Zeeman effect is described theoretically.
