Experimental artifact in MOKE measurements when using paramagnetic sample holders

We describe here an artifact that may affect to magneto-optical Kerr measurements. When paramagnetic sample holders (SH) with non-negligible susceptibilities are used, the inhomogeneity of the applied magnetic field can induce forces and torques on it, shifting the reflected beam, and altering its intensity at the photodetector. The effect is even and can be avoided using low susceptibility paramagnetic or diamagnetic SH We also present a detailed analytical description of the magnetic forces involved and provide some estimated values of the SH shifting, showing that they might distort the magneto-optical Kerr effect signal. Moreover, in this paper we show how the artifact can be removed from the experimental curves with an appropriated data analysis.Fil: Munoz-Noval, Alvaro. Comunidad de Madrid; EspañaFil: Bonin, Claudio Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Bonetto, Fernando Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Física del Litoral. Universidad Nacional del Litoral. Instituto de Física del Litoral; ArgentinaFil: Garcia, Miguel Angel. Institute For Ceramic And Glass; Españ

The A-cation deficient perovskite series La_2-xCoTiO_6-δ (0 ≤ x ≤ 0.20): new components for potential SOFC composite cathodes

The best performances are obtained for low x due to a compromise between sufficiently high amount of defects, but not so high to induce defect clustering.</p

Photoassisted Immersion Deposition of Cu Clusters onto Porous Silicon: A Langmuir-Hill Ligand-Locus Model Applied to the Growth Kinetics

Cu-porous silicon (Cu-PS) composite materials consisting of nanosized Cu dusters preferentially grown on the surface of PS were fabricated by photoassisted deposition of Cu nanoparticles onto PS. Structural and chemical characterization of the Cu particles grown in the PS matrix has been carried out by synchrotron X-ray absorption spectroscopy, from which different reaction stages have been identified within the photoassisted reaction. In particular, it was found that the reduction of Cu occurs in three main phases: (a) Cu nucleates homogeneously in a few seconds over the surface of PS by a coupled red-ox reaction; (b) clusters grow by new reduced ions, which tend to oxidize the previously deposited Cu atoms making increasingly heterogeneous Cu clusters; and (c) a competitive process between nucleation of new dusters and cluster coalescence gives rise to a bulklike Cu thin film. It was determined that the structures formed in the first two phases display surface plasmon resonance, with band intensity and broadening consistent with the increasing heterogeneity of the clusters. The growth kinetics has been fitted to a Langmuir-Hill model. Following these results, a reaction model has been proposed to explain the mechanisms involved in the first stages of Cu dustering