Resonant L_alpha,betha X-ray emission and L2,3 X-ray absorption spectra of 3d metals in Co2MnZ (Z=Al,Ga,Sn,Sb) Heusler alloys as an element-selectve probe of spin character of valence band
2005 (English)In: Journal of Electron Spectroscopy and Related Phenomena, ISSN 0368-2048, Vol. 144-147, 765-769 p.Article in journal (Refereed) Published
The 3d metal resonant X-ray emission spectra (RXES) and L3,2 X-ray absorption spectra (XAS) of the Co2MnZ (Z=Al, Ga, Sn, Sb) alloys were measured using linearly polarized soft X-rays. The Mn and Co spectra are compared with results of spin-polarized calculations of Mn 3d and Co 3d partial densities of states performed for each alloy. It is found that a satellite observed at the high-energy side of Mn spectra is due to the localized Mn 3d states located above the Fermi energy. It is shown that the presence of the same satellite structure indicates a higher degree of spin-polarization of Mn 3d states than Co 3d states.
Both the intensity of the satellite structure in Mn spectra and the /, peak ratio are increased and follow the atomic number of Z element. The effect is especially strong when excitating slightly above the L3 and L2 threshold energies as well as at resonance. We observe a correlation between these spectral parameters and the magnitude of local magnetic moment. The changes occurring in the Mn RXES are in good agreement with a predicted decrease in p–d hybridization (between the atoms of Z element and Mn atoms). The calculated local density of Mn 3d states at the Fermi energy follows the same trend as the hybridization. This suggests that RXES of 3d metals can be used to monitor the degree of spin-polarization of the valence band states and the local density of states at the Fermi level. Note that neither the Mn L2,3 absorption nor the Co L2,3 and Co emission spectra of the alloys are affected by the different composition (different Z elements).
Place, publisher, year, edition, pages
2005. Vol. 144-147, 765-769 p.
X-ray emission spectra and fluorescence; Local moment in compounds and alloys; Spin arrangements in magnetically ordered materials
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:uu:diva-237940DOI: 10.1016/j.elspec.2005.01.064OAI: oai:DiVA.org:uu-237940DiVA: diva2:769427