INSTITUTO DE FISICA LA PLATA
Unidad Ejecutora - UE
congresos y reuniones científicas
Identification of Impurity Atoms in Electrodeposited Films And Milled Powders of ZnMO (M=Co, Mn)
J.HOYA; J.I.LABORDE; M.MEYER; L. C. DAMONTE; L.A. MENDOZA-ZÉLIS
Conferencia; he 5th Latin American Conference on Metastable and Nanostructured Materials NANOMAT 2012; 2012
Recently lot of work has been focused on (Zn, Mn)O and (Zn, Co)O which appears as new promising materials for spintronic. Some authors observed ferromagnetic behavior even at room temperature in these so called diluted magnetic semiconductors (DMS) materials, but the origin of this behavior is being controversial. Some have claimed that the origin of ferromagnetism is related to the formation of Co-rich clusters, but the source of the observed ferromagnetism is far for being clear. In previous works, we have analyzed the magnetic properties on mechanical milled  and electrodeposited films  of ZnMnO or ZnCoO samples. In these cases, ZnCoO samples are paramagnetic, what in principle is an indication of a homogeneous distribution of Co into the ZnO matrix. However ZnMnO reveals an antiferromagnetic behavior for high contents of Mn. Therefore taking advantage of synchrotron capabilities that allow us the possibility of residual elemental detection inside Mn-rich or Co-rich clusters, in this work, we present EXAFS characterization of these Zn1−xMxO (M: Mn, Fe and Co) samples. The results are discussed taking into account previous studies made by X-ray diffraction, Mössbauer Spectroscopy and magnetic measurements in a Quantum Design MPMS-5S superconducting quantum interference device (SQUID) magnetometer.