Element-specific magnetic moments from core-absorption magnetic circular dichroism of the doped Heusler alloyCo2Cr0.6

Abstract

The magnetic circular dichroism ͑MCD͒ of core-level absorption ͑x-ray absorption spectroscopy, XAS͒ spectra in the soft x-ray region has been measured for the ferromagnetic Heusler alloy Co 2 Cr 0.6 Fe 0.4 Al at the Co, Fe, and Cr L II,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.

Antiferromagnetic dipolar ordering in[Co2MnGe∕V]Nmultilayers

“…Comparable results were also discovered for the full Heusler compound Co 2 Cr 1−x Fe x Al [83,84]. While a partial exchange of Cr/Fe atoms with Al leaves the half-metallicity unaffected, an exchange of Co atoms with Cr, Fe or Al destroys the half-metallicity.…”

Electronic structure and spectroscopy of the quaternary Heusler alloy Co2Cr1−xFexAl

“…Details of the spectroscopy experiments are reported below. The values were found from a sum rule analysis neglecting the magnetic dipole term [36]. The calculated spin magnetic moments at the Co sites increase with increasing Fe concentration x as result of the shift of the majority PDOS of Co.…”

“…The entrance and exit slits of the monochromator were set symmetrically in the range from 10µm to 25µm resulting in a resolution of about 50meV at the different absorption edges. Details of the data analysis are reported in [36].…”

“…In particular, the L 2,3 edges of the ferromagnetic 3d transition metals are easily accessible in the soft X-ray range (500eV to 800eV) as they exhibit pronounced white lines. X-ray magnetic circular dichroism (XMCD) [35,36] was used in the present work to study the site specific magnetic moments in Co 2 Cr 1−x Fe x Al.…”

Epitaxial growth of Co2Cr0.6Fe0.4Al Heusler alloy thin films on MgO (0 0 1) substrates by magnetron

“…Cobalt-based full-Heusler alloys have been considered potential candidates for showing HMF properties. Their structural and magnetic properties have been intensively investigated experimentally [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and theoretically [19][20][21][22][23] because they have comparatively high Curie temperatures T C . In particular, Co 2 Cr 1−x Fe x Al (CCFA) is expected to have suitable electro-magnetic properties for injecting a spinpolarized current [16,22].…”