Determination of the cation site distribution of the spinel in multiferroic CoFe2O4 / BaTiO3 layers by X-ray photoelectron spectroscopy

T. Aghavnian (1, 2) , J.-B. Moussy (1) , D. Stanescu (1) , Rachid Belkhou (2) , N Jedrecy (3) , Hélène Magnan (1) , P. Ohresser (2) , Arrio M.-A. (4) , Ph. Sainctavit (4) , Antoine Barbier (1)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 SSOLEIL - Synchrotron SOLEIL
3 INSP - Institut des Nanosciences de Paris
4 IMPMC - Institut de minéralogie et de physique des milieux condensés

The properties of CoFe2O4/BaTiO3 artificial multiferroic multilayers strongly depend on the crystalline structure, the stoichiometry and the cation distribution between octahedral (Oh) and tetrahedral (Td) sites (inversion factor). In the present study, we have investigated epitaxial CoFe2O4 layers grown on BaTiO3, with different Co/Fe ratios. We determined the cation distribution in our samples by X-ray magnetic circular dichroism (XMCD), a well accepted method to do so, and by X-ray photoelectron spectroscopy (XPS), using a fitting method based on physical considerations. We observed that our XPS approach converged on results consistent with XMCD measurements made on the same samples. Thus, within a careful decomposition based on individual chemical environments it is shown that XPS is fully able to determine the actual inversion factor.

Mots clés: X-ray magnetic circular dichroism (XMCD); Cation distribution; X-ray photoelectron spectroscopy (XPS); Oxides; Ferrites

Domaines: Physique [physics]

T. Aghavnian, J.-B. Moussy, D. Stanescu, Rachid Belkhou, N Jedrecy, et al.. Determination of the cation site distribution of the spinel in multiferroic CoFe2O4 / BaTiO3 layers by X-ray photoelectron spectroscopy . Journal of Electron Spectroscopy and Related Phenomena, 2015, 202, pp.16-21. ⟨10.1016/j.elspec.2015.02.006⟩. ⟨cea-01365822⟩