Quantum Interference Effect on the Conductance of a Ferromagnetic Wire with a Domain Wall

Abstract

We study quantum interference corrections to the conductance of a thin wire of a disordered ferromagnetic metal in the presence of a domain wall (DW). The DW is a source of the decoherence of electron wavefunctions. We calculate the weak-localization correction and the mesoscopic conductance fluctuations to show how the DW suppresses these quantum corrections. We explicitly take the location of the DW into account in calculating the quantum corrections. It is shown that the magnitude of the quantum corrections depends on the location of the DW when the system length is of the order of, or shorter than, the phase coherence length. We find that the quantum interference corrections are most remarkably suppressed when the DW is located at the center of the ferromagnetic wire. It is also shown that the decoherence effect becomes pronounced with decrease of the thickness of the DW.