A and B-site magnetic contributions in ferrimagnetic ZnFe2O4 thin film and nanoparticles studied using XMCD

C. RODRÍGUEZ TORRES; P. MENDOZA ZÉLIS; G. PASQUEVICH; S. J. STEWART

Encuentro; RAU Reunión Anual de Usuarios de LNLS; 2012

The local magnetic properties at room temperature of ZnFe2O4 ferrites in film and nanopowders forms, having different cations distribution and oxygen vacancies concentrations, were studied by x-ray magnetic circular dichorism (XMCD) at the L2,3 edges of Fe. The results show that the dichroic signal is markedly large when the magnetic contribution of iron ions at octahedral spinel B-sites prevails, resulting in a 40% larger magnetic moment per iron ion. Our results indicate that the magnetic properties of the studied ferrites depend on the distribution of cations imposed by the presence of oxygen vacancies. The latter is complemented by the absence of Zn2+ nonmagnetic ions at octahedral sites, the overpopulation of tetrahedral A-sites by Fe3+ and Zn2+ as well as octahedral vacancies in the ZnFe2O4 film.