ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Recently it was shown that the electrical resistivity behaves anomalously both at low temperatures and near the Curie point in rare-earth iron borides due to the subtle interplay between 4f and 3d transition elements. Here a systematic experimental study on the behavior of the thermoelectric power (S) of R2Fe14B compounds with heavy (R=Gd, Tb, Dy, Ho, Er) and light (Nd, Sm) rare-earth elements is presented. Data for La2Fe14B, in the temperature range 10 K〈T〈350 K, is also included for comparison. The results are consistent with the spin-mixing model for electron scattering, with an intrinsic thermopower contribution related to Fe and a spin dependent impurity scattering term related to the rare-earth magnetic ions. From the interplay of both terms we can get maxima in S (for R=Td, Dy, Ho, Er samples) or minima (Gd, Nd, Sm) at low temperatures. The data indicates the ultimate dominance of impurity scattering at low temperatures, producing a linear variation in the magnetic thermopower (S). In La2Fe14B, only the intrinsic effect is observed, and S(T) does not follow a linear temperature dependence.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.358091
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