Resistivity due to a Domain Wall in Ferromagnetic Metal

TL;DR

This paper calculates how a domain wall in a ferromagnetic metal affects electrical resistivity, showing that domain walls can reduce resistivity and influence conductance fluctuations, with results aligning with recent experiments.

Contribution

It introduces a quantum correction framework for resistivity due to domain walls using gauge theory, highlighting the wall's role in electron decoherence and conductance fluctuations.

Findings

Domain walls contribute to electron decoherence.

Quantum corrections can surpass classical resistivity.

Wall motion causes conductance fluctuations.

Abstract

The resistivity due to a domain wall in ferromagnetic metallic wire is calculated based on the linear response theory. The interaction between conduction electrons and the wall is expressed in terms of a classical gauge field which is introduced by the local gauge transformation in the electron spin space. It is shown that the wall contributes to the decoherence of electrons and that this quantum correction can dominate over the Boltzmann resisitivity, leading to a decrease of resisitivity by nucleation of a wall. The conductance fluctuation due to the motion of the wall is also investigated. The results are compared with recent experiments.