About the magnetism in pure SnO2 and TiO2 oxides thin films

GOLMAR, F; MUDARRA NAVARRO, A.; RODRÍGUEZ TORRES, C.E; CABRERA, A.F; SACCONE, F.,; SÁNCHEZ, F.H.

Buenos Aires

Congreso; FMC2006-At the Frontiers of Condensed Matter, II Magnetism, Magnetic Materials and Their Applications; 2006

CNEA

Recently, interesting results were reported showing room temperature ferromagnetism on pure TiO2, HfO2, SnO2 and In2O3 oxide films[2, 3, 4] and also in films doped with non-magnetic impurities [5]. They assume that defect, especially oxygen vacancies could be the reason of the observed magnetism. The saturation magnetization is in all cases in the order 20-30 emu/cm3 and the magnetic moment (in films deposited on LaAlO3 with a surface of 0.5x0.5 cm2) in the order of 105 emu. In this work we present a study of the magnetic properties of pure SnO2 and TiO2 thin films deposited on LaAlO3 by pulsed laser deposition (PLD) that result ferromagnetic at room temperature. We explore the influence of deposition, cleaning of the films previous to the magnetic measurement and substrate treatment conditions on the presence of magnetism in these samples. The samples were characterized by X-ray diffraction (XRD) and magnetometer measurements performed using a SQUID. [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] C.E. Rodríguez Torres, L. Errico, F. Golmar, A.M. Navarro Mudarra, A.F. Cabrera, S. Duhalde, F.H. Sánchez, and M. Weissmann, JMMM (2006), in press. [6] 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).