The Fe1−xVx alloy system exhibits the lowest known Gilbert relaxation rate of any ferromagnetic metal or binary alloy with G = 35 MHz at x = 27% V. Low relaxation rates are of particular interest in modern spin electronic applications involving spin torque. The transport spin polarization of a series of sputtered epitaxial Fe1−xVx samples was measured using point contactAndreev reflection. Values of the transport spin polarization agree well with those measured for pure Fe and are independent of composition. The results indicate that the substitution of up to 50% of V for Fe does not reduce the spin polarization in the alloy.
Received 22 October 2012Accepted 16 May 2013Published online 30 May 2013
The authors wish to acknowledge I. Mazin for discussions on the LAPW calculation and for providing the PCAR fitting routine. We also acknowledge K. Jensen for modifying the fitting routine. W.E.B. acknowledges the National Science Foundation (Grant No. U.S. NSF-ECCS-0925829) and the Army Research Office (Grant No. DAW911NF-07-1-0326) for support. D.P. acknowledges the financial support of the ORNL LDRD SEED program project S12-006, “Rare-Earth-Free Magnets: Compute, Create, Characterize”.