Paramagnon drag

Sph and are the contributions to the thermopower due to electron diffusion, phonon drag and magnon drag (or paramagnon drag), respectively. 

At this point is should be mentioned that there are minima in S versus T observable at low temperatures in most of the known spin-fluctuation systems (e.g., UAlj, YCoj, LuCo2, etc.). Although there is no theoretical confirmation, it is conceivable that the paramagnon drag is the reason for these experimentally observed minima in S versus T. 

Although it is as yet unknown whether paramagnon-drag effects have an influence on the temperature variation of the thermopower, it is at least imaginable that the experimentally observed low-temperature minima in S versus T are due to such a drag effect. 

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