Anisotropic magnetoresistance in a two-dimensional electron system with Rashba and Dresselhaus spin-orbit coupling

We systematically study the anisotropic magnetoresistance (AMR) in a two-dimensional electron system with a combined Rashba and Dresselhaus spin-orbit interaction by exactly solving the kinetic equation. This AMR originates from the combination of spin-orbit coupling and in-plane magnetization, instead of the combined effect of spin-orbit coupling and polarized impurities emphasized in previous theoretical studies. A combined electromagnetic potential is taken into account to investigate the effect of impurity scattering. The electric component of the potential is long ranged, and both the positions and the directions of the magnetic moments of magnetic impurities are random. For long-range electric collision, AMR occurs and AMRs due to remote charged scatterers and background ones are comparable. For pure magnetic scattering, the magnitude of AMR is tiny when the magnetization is smaller than a singular magnetization. However, the anisotropy of spin-spin coupling can enhance the AMR and its magnitude reaches up to nearly 100% when only the majority band is occupied. For the combined electromagnetic potential, the magnitude of AMR is not very large and its sign is always positive when the electric part of scattering is remote. A sudden step of AMR emerges when the value of magnetization is near the Fermi energy, which is due to the uncontinuity of the density of state.