Mesoscopic effects in the thermopower of dilute AuFe alloys
We have employed electron heating experiments, and noise thermometry to perform quantitative measurements of the thermopower in mesoscopic samples. This new measuring technique allows to detect finite size effects in the thermopower of narrow AuFe wires with an Fe concentration ranging from 50 to 3000 ppm. The size effects emerge when reducing the width of the wires below ≅300 nm. Our observations can be understood in terms of a magnetic anisotropy which affects the spins close to the surface of the sample. The spin glass freezing at lower temperatures suppresses the size effects.
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- Here we assume that the magnetic TEP dominates all other contributions, which is well justified for dilute magnetic alloys .Google Scholar