Exploiting magnetic properties of Fe doping in zirconia

In this study we explore, both from theoretical and experimental side, the effect of Fe doping in ZrO<Subscript>2</Subscript> (ZrO<Subscript>2</Subscript>:Fe). By means of first principles simulation, we study the magnetization density and the magnetic interaction between Fe atoms. We also consider how this is affected by the presence of oxygen vacancies and compare our findings with models based on impurity band [J.M.D. Coey, M. Venkatesan, C.B. Fitzgerald, Nat. Mater. <Emphasis Type="Bold">4, 173 (2005)] and carrier mediated magnetic interaction [T. Dietl, H. Ohno, F. Matsukura, J. Cibert, D. Ferrand, Science <Emphasis Type="Bold">287, 1019 (2000)]. Experimentally, thin films (≈20 nm) of ZrO<Subscript>2</Subscript>:Fe at high doping concentration are grown by atomic layer deposition. We provide experimental evidence that Fe is uniformly distributed in the ZrO<Subscript>2</Subscript> by transmission electron microscopy and energy dispersive X-ray mapping, while X-ray diffraction evidences the presence of the fluorite crystal structure. Alternating gradient force magnetometer measurements show magnetic signal at room temperature, however, with low magnetic moment per atom. Results from experimental measures and theoretical simulations are compared. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2013