Change in resistance of CuFe wires induced by spin injection

Spin injection from a ferromagnetic metal Co into a Kondo alloy CuFe is demonstrated using the devices with a Co/CuFe wire junction. The temperature dependent resistivity of CuFe shows an increase below 20 K as spin current flows from CuFe into Co as seen in Kondo alloys. In contrast, the resistivity for the opposite current direction from Co into CuFe decreases at low temperatures at a current of 250 μA. The difference between the resistivities of both the current directions logarithmically increases with decreasing temperature, indicating the suppression of the spin scattering at Fe impurities that causes the logarithmic increase in Kondo alloys.