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Schlagwörter:
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Zusammenfassung:
The magnetic circular dichroism (MCD) of core-level absorption (x-ray
absorption spectroscopy, XAS) spectra in the soft x-ray region has been
measured for the ferromagnetic Heusler alloy Co2Cr0.6Fe0.4Al at the Co,
Fe, and Cr L-II,L-III edges. The comparison of XAS spectra before and
after in situ cleaning of polished surfaces revealed a pronounced
selective oxidation of Cr in air. For clean surfaces we observed a MCD
for all three elements with Fe showing the largest moment per atom. The
MCD can be explained by the density of states of the 3d unoccupied
states, predicted by linear muffin-tin orbital atomic sphere
approximation. For Fe and Cr the orbital angular momentum component of
the magnetic moment is considerably larger than the values reported for
metallic alloys, whereas for Co a value close to its bulk value is
observed. This observation is discussed in comparison with band
structure calculations.