XAS and XMCD studies of amorphous FeCo-based ribbons

Investigation on cation distribution and luminescence in spinel phase γ-Ga3−δO4 : Sm nanostructures using X-ray absorption spectroscopy

“…In this regard, X-ray absorption spectroscopy (XAS), with its two branches of X-ray absorption near edge structure (XANES) and extended X-ray absorption ne structure (EXAFS), becomes the important elemental characterization technique and has been known to be highly sensitive to the local electronic/atomic structure properties and effectively overcomes the issue of sensitivity to the structure and electronic structure characterization of small sized, poorly crystalline or embedded nanostructures. [26][27][28] In the last few years, probing the local symmetry of the diluted doped elements, 29,30 quantication of the valence state changes of host metal ions upon foreign element doping, [31][32][33] changes in the orbital occupancy, 34,35 and variation in the crystal eld effects 36,37 have been studied for various compounds using the XANES. On the other side, EXAFS, due to the sensitivity to the local atomic structure, has become a powerful probing tool for determining the variation in the coordination number and bond lengths of the constituent elements of the probed material.…”

Chemical Structure and Magnetism of FeOx/Fe2O3 Interface Studied by X-ray Absorption Spectroscopy

“…No such peaks were reported in stoichiometric oxides, including FeO, Fe3O4, or Fe2O3 [21,[34][35][36][37][38]. Therefore, the high energy states should be attributed to an additional energy level splitting due to a lower Fe-O coordination symmetry, which can be the case of sub-stoichiometric oxide, FeOx<1 [9,32,39,40]. The formation of FeOx at the Fe/Fe2O3 interface is plausible because Fe-oxides are generally more stable than Fe metal thermodynamically, and O would be easily supplied by Fe2O3 to partially oxidize Fe near the interface region.…”

Highly Enhanced Curie Temperature in Ga‐Implanted Fe3GeTe2 van der Waals Material

“…The XAS from the Fe absorption edge, however, show little change with the Ga + exposure time (Figure 2h). Therefore we conclude that either the amorphized Fe 3 GeTe 2 has almost identical Fe spectra as in un‐irradiated Fe 3 GeTe 2 , [ 22 ] or Ga amount is too tiny to change the valence state of the Fe atoms in Fe 3 GeTe 2 . Then the interesting question is whether the ferromagnetic state shown in Figure 1 is from the majority Fe atoms in Fe 3 GeTe 2 or from the tiny amount of Fe atoms around the implanted Ga ions?…”