Spin dependent transport in manganite-based metallic multilayers

M. GRANADA; J. C. ROJAS SÁNCHEZ; L. B. STEREN; A. G. LEYVA

Reñaca, Chile

Workshop; VII Latin American Workshop on Magnetism, Magnetic Materials and their Applications; 2005

The study of magnetoresistive systems has attracted the attention in the last decades due to their potential application in spintronics, i.e. devices in which the charge carriers are spin-polarized. At present, the magnetoresistive heads are based on the giant magnetoresistance (GMR) effect present in ferromagnetic metal (FM) /non-magnetic metal (NM) multilayers. The magnitude of this effect depends on the properties of each material used as a component, as well as on the interfaces. In this work we explore structural and magnetotransport properties of La0.75Sr0.25MnO3 (LSMO) / LaNiO3 (LNO) multilayers. LSMO is a FM manganite with nearly 100% spin polarization, which makes it a good candidate for GMR devices. LNO is a NM metal with lattice constant very similar to that of LSMO, so that good quality superlattices can be obtained. The X-ray diffraction patterns of the samples put in evidence the good stacking of the layers. We have determined the critical layer thickness of LNO in order to obtain magnetic decoupling and studied the anisotropies of the magnetic layer. We will also present some recent results on electric transport in these multilayers, as a function of temperature and magnetic field.