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Quantum coherence in a ferromagnetic metal: time-dependent conductance fluctuations

S. Lee·A. Trionfi·D. Natelson
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Abstract

Quantum coherence of electrons in ferromagnetic metals is difficult to assess experimentally. We report the first measurements of time-dependent universal conductance fluctuations in ferromagnetic metal (Ni$_{0.8}$Fe$_{0.2}$) nanostructures as a function of temperature and magnetic field strength and orientation. We find that the cooperon contribution to this quantum correction is suppressed, and that domain wall motion can be a source of coherence-enhanced conductance fluctuations. The fluctuations are more strongly temperature dependent than those in normal metals, hinting that an unusual dephasing mechanism may be at work.

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S. Lee, A. Trionfi, D. Natelson. 2004-08-10. Quantum coherence in a ferromagnetic metal: time-dependent conductance fluctuations. https://doi.org/10.1103/physrevb.70.212407

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