  The longitudinal spin Seebeck effect is measured on the ferromagnetic
insulator Fe$_3$O$_4$ with the ferromagnetic metal
Co$_{0.2}$Fe$_{0.6}$B$_{0.2}$ (CoFeB) as the spin detector. By using a
non-magnetic spacer material between the two materials (Ti), it is possible to
decouple the two ferromagnetic materials and directly observe pure spin flow
from Fe$_3$O$_4$ into CoFeB. It is shown, that in a single ferromagnetic metal
the inverse spin Hall effect (ISHE) and anomalous Nernst effect (ANE) can occur
simultaneously with opposite polarity. Using this and the large difference in
the coercive fields between the two magnets, it is possible to unambiguously
separate the contributions of the spin Seebeck effect from the ANE and observe
the degree to which each effect contributes to the total response. These
experiments show conclusively that the ISHE and ANE in CoFeB are separate
phenomena with different origins and can coexist in the same material with
opposite response to a thermal gradient.
