Thermopower of RB12 dodecaborides (R = Ho, Er, Tm, Lu)

Detailed measurements of the Seebeck coefficient S(T) in a broad range of temperatures (T = 2–300 K) have been performed for the first time for RB12 dodecaborides (R = Ho, Er, Tm, Lu) in paramagnetic (diamagnetic for LuB12) and antiferromagnetic states. At intermediate temperatures (10–300 K), the thermopower is determined by the interaction of carriers with phonon modes, which are related to the oscillations of rare-earth atoms in the framework of atomic clusters B12. A comparative analysis of the parameters determining photon drag the thermopower related to the phonon drag and the results of galvanomagnetic measurements shows evidence for a significant effect of spin fluctuations on the behavior of charge transport characteristics in RB12 compounds with strong electron correlations.