Short range order of spin moments in NdCo2 studied by magnetic EXAFS

Magnetic Extended X-tay Absorption Fine Structure (MEXAFS) is a dichroic co ntribution to an x-ray absorption. The MEXAFS has been measured at Co K-edg e in NdCo2 and at Fe EC-edge in iron thin film The Fourier analysis was car ried out to obtain information about local magnetic structures in these sys tems. The positions and the sign of peaks in the imaginary part of Fourier transformed MEXAFS show a good agreement with those of conventional EXAFS f or the iron thin film. In the case of NdCo2, the peak position for the near est Nd shell was 2.89 Angstrom in the imaginary part of Fourier transformed MEXAFS, which is the same sign with corresponding peak in EXAFS. The fact that the sign of the peak was positive for the spin moments of Nd, which wa s not the absorption element, can be explained that the spin polarization o f photoelectrons outgoing from the absorbing atoms is antiparallel to that of an absorbing Co atom in NdCo2.