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Mesoscopic Resistance Fluctuations in Cobalt Nanoparticles

Y. G. Wei·X. Y. Liu·L. Y. Zhang·D. Davidović
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Abstract

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 $\approx 5π$. 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, $τ_ϕ\sim ps$, which we attribute to the strong magnetocrystalline anisotropy.

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Y. G. Wei, X. Y. Liu, L. Y. Zhang, D. Davidović. 2006-04-26. Mesoscopic Resistance Fluctuations in Cobalt Nanoparticles. https://doi.org/10.1103/physrevlett.96.146803

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