Mn L-2,L-3-edge EXAFS and Magnetic EXAFS Studies on the Halfmetallic Ferromagnet Co2MnSi

We report the magnetic circular dichroism in the extended x-ray absorption fine structure (EXAFS) in a prototypical halfmetallic ferromagnet Co2MnSi. The EXAFS oscillations at the Mn L-2,L-3 edges are analyzed to obtain parameters used in the analysis of the magnetic EXAFS (MEXAFS). Theoretical calculations of MEXAFS spectra in Co2MnSi show that the linear-path scatterings have larger contributions than the multiple triangular-path scatterings. Furthermore, the period of the oscillations in the MEXAFS spectra is shorter than that in the EXAFS spectra indicating that the far site contributions from the second to the fourth nearest neighbor Co and the third nearest Si atoms can strongly influence the MEXAFS oscillations, while the Mn atoms, despite the large magnetic moment, can have little contributions due to the interference of the spin components.