Distinguishing magnetic moment & magnetic-ordering on the Slater-Pauling curve
Abstract
We report magnetic dichroism in photoemission using linearly-polarized synchrotron radiation at the Advance Light Source, Berkeley (XMLD) from the 3p core levels of the ferromagnetic metals Fe, Co, Ni, and their binary alloys, including Cu. Lineshape analysis reveals that the magnetic dichroism asymmetry in the spectral width, W(xmld), tracks the changing magnitudes of the elemental magnetic moments. In contrast, the magnetic dichroism asymmetry peak-to-peak amplitudes, A(xmld), monitor the overall saturation magnetization. While W(xmld) tracks the Slater-Pauling curve showing the variation of atomic moments with unpaired valence electrons, A(xmld) shows variations due to changing magnetic anisotropy and magnetic disorder. Experimental results for both fcc and bcc Fe(x)Ni(1-x) alloys reveal the origin of the 'Invar Instability' around x = 65% is due to non-colinear disordering of the moments [1]. That is A(xmld) for these elements shows strong deviation from the Slater-Pauling moments curve. [1] F.O. Schumann, R.F. Willis, K.G. Goodman & J.G. Tobin Phys. Rev. Lett. vol. 79, 5166 (1997).
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARL23011W