Magnetism in SnO2 and TiO2 thin films obtained by PLD

F. GOLMAR; A.M. MUDARRA NAVARRO; C.E. RODRÍGUEZ TORRES; A.F. CABRERA; S. DUHALDE; F.H. SÁNCHEZ

Bariloche

Congreso; ICSFS; 2006

A variety of semiconducting materials, called diluted magnetic semiconductors (DMS) combine two properties: semiconductivity and magnetism. Many research groups have focused on doping TiO2 with transition metals. Thus much of the work has concentrated on Co-doped TiO2 films, where at room temperature ferromagnetism has been confirmed first for anatase and later also for rutile films. Recently, Co, Fe, Ni and Mn doped SnO2 have been explored and interesting results were reported, especially in the case of the Co doped system where a giant magnetic moment was found (7.5 mB/Co at. at room temperature) [1]. On the other hand some authors have reported remarkable room temperature ferromagnetism on pure TiO2, HfO2 and In2O3 oxides films [2, 3] and also in films doped with non-magnetic impurities [4]. In this work we present a study of the magnetic properties of pure and Fe-doped SnO2 and pure and Cu-doped TiO2 thin films deposited on LaAlO3 by pulsed laser deposition (PLD). The samples were characterized by X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD) and the magnetic properties were measured using a SQUID. Finally, ab-initio calculations, using full potential linear augmented plane wave (FP-LAPW) method, were performed. Theoretical and experimental results are compared and discussed. [1] S.B. Ogale et. al., Phys. Rev. Let. 91 (2003) 077205.     [2] C. B. Fitzgerald, M. Venkatesan, A. P. Douvalis, S. Huber, J. M. D. Coey, and T. Bakas, J. Appl. Phys. 95(11) (2004) 7390. [4] N. H. Hong, J. Sakai, W. Prellier and A. Hassini, J. Phys.: Condens. Matter 17 (2005) 1697. [5] Duhalde S, Vignolo M F, Golmar F, Chiliotte C, Rodríguez Torres C E, Errico L A, Cabrera A F, Rentería M, Sánchez F H and Weissmann M Phys. Rev. B  72 (2005) 161313(R).