HIGH ENERGY RESOLUTION MAGNETIC CIRCULAR DICHROISM MEASUREMENT OF THE FERRITE FAMILY

Abstract

Magnetic circular dichroism (MCD) spectra of spinel ferrites MFe 2 O 4 (M = Co, Mn, Fe, Co and Ni) have been measured by using a photon-helicity-switching method. The method achieves high energy resolution and a low noise-to-signal ratio. The Fe L2,3 absorption spectra of MFe 2 O 4 show a similar spectral profile; on the other hand, the MCD spectra show the characteristic fine structures. These differences are attributed to the variety of 3d electron configuration of Fe ions ( Fe 2+ or Fe 3+) and the local symmetry (tetrahedral or octahedral). The origin of the positive peak of MFe 2 O 4 (M = Fe, Co and Ni) MCD spectra at the L3 edge is attributed to the tetrahedral Fe 3+ (3d5) state.