Recently we reported on the differential resistance R(I) = dV/dI of narrow AuFe spin-glass wires (Phys. Rev. Let., 77 (1996) 2276). Surprisingly, R(I) was found to be asymmetric in I for the smallest samples. In this letter we present differential resistance measurements performed on a AuFe wire with a multiprobe geometry. The new experiments reveal that the asymmetric behavior of R(I) can be explained in terms of a mesoscopic thermoelectric effect. Our experiments also indicate that the therrnopower S of a AuFe spin-glass alloy becomes size dependent for length scales below a few hundred nanometers.
ASJC Scopus subject areas
- Physics and Astronomy(all)