We present measurements of mesoscopic resistance fluctuations in cobalt nanoparticles and study how the fluctuations with bias voltage, bias fingerprints, respond to magnetization reversal processes. Bias fingerprints rearrange when domains are nucleated or annihilated. The domain-wall causes an electron wavefunction phase-shift of ≈5π. The phase-shift is not caused by the Aharonov-Bohm effect; we explain how it arises from the mistracking effect, where electron spins lag in orientation with respect to the moments inside the domain-wall. Dephasing time in Co at 0.03K is short, τϕ∼ps, which we attribute to the strong magnetocrystalline anisotropy.
@article{arxiv.cond-mat/0509452,
title = {Mesoscopic Resistance Fluctuations in Cobalt Nanoparticles},
author = {Y. G. Wei and X. Y. Liu and L. Y. Zhang and D. Davidović},
journal= {arXiv preprint arXiv:cond-mat/0509452},
year = {2009}
}