Evidence of Spin-Polarized Current in Fe-Rich NbFe2 Compound

The effects of slight changes in the ideal stoichiometry on the structural, magnetic properties, and electrical transport of
$\text{Nb}_1-x\text{Fe}_{2+x}(x>0)$
compounds have been investigated. Excess Fe in
$\text{Nb}_1-x\text{Fe}_{2+x}$
leads to an anisotropic contraction of the unit cell: the initial growth along the
$a$
and b-axis achieves a maximum for sample A2 while c-axis increase continously. The magnetotransport results in the
$\text{NbFe}_{2}$
compound with an excess of Fe highlight the presence of a spin-polarized current in these compounds. The correlation between the electrical transport and X-ray diffraction results suggests changes in the Fermi surface induced by Fe excess.