FNA Annual Report 2010 - Technische Universiteit Eindhoven

FNA Annual Report 2010 6.Results 33
Output
Local formation of a Heusler structure in CoFe-Al alloys
S. Wurmehl, P.J. Jacobs, J.T. Kohlhepp, H.J.M. Swagten, B. Koopmans, S. Maat, M.J. Carey, and J.R. Childress
Applied Physics Letters 98, 012506 (2011)
Fig. 1 Left: 59 Co NMR spectrum of a CoFe-
Al sample with 25 at.% Al, also shown is
the corresponding fit with Gaussian lines
for the different next neighbor (Fe, Al)
environments of the Co nuclei.
Right: Comparison between a random
atom model and the relative areas of each
resonance line in the fit, hinting to the
formation of the local formation of a
Heusler type structure.
Fig. 2
59
Co NMR spectra for several studied
samples.
Fig. 3 Comparison between the CPP-GMR properties and the
contribution of the highly spin-polarized Heusler compound both
as a function of the Al content of the
samples.