Domain wall magnetoresistance in a quantum wire

Abstract

A theory is suggested in this study which predicts both positive and negative magnetoresistances (MRs) due to the domain wall (DW) in weak magnetic fields. The analysis showed two distinct regimes which are specified by the impurity density, the Fermi wave vector of the system and the external magnetic field. These two regimes correspond to positive and negative MRs. When the Zeeman interaction strength is comparable to the impurity scattering amplitude at Fermi level, the contribution of the DW to MR should be negative, also it can be shown analytically that, in contrast to the pure system for an impure DW, MR is not symmetric for magnetic fields which are parallel or anti-parallel to the DW rotation axis, and for a pure DW, the contribution to the MR is always positive.