Publications by authors named "Mechin L"

We present the design, fabrication, and characterization of an implantable neural interface based on anisotropic magnetoresistive (AMR) magnetic-field sensors that combine reduced size and high performance at body temperature. The sensors are based on LaSrMnO (LSMO) as a ferromagnetic material, whose epitaxial growth has been suitably engineered to get uniaxial anisotropy and large AMR output together with low noise even at low frequencies. The performance of LSMO sensors of different film thickness and at different temperatures close to 37 °C has to be explored to find an optimum sensitivity of ∼400%/T (with typical detectivity values of 2 nT·Hz at a frequency of 1 Hz and 0.

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The structural, electronic, and magnetic properties of Sr-hole-doped epitaxial La Sr MnO (0.15 ≤ ≤ 0.45) thin films deposited using the molecular beam epitaxy technique on 4° vicinal STO (001) substrates are probed by the combination of X-ray diffraction and various synchrotron-based spectroscopy techniques.

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The properties of half-metallic manganite thin films depend on the composition and structure in the atomic scale, and consequently, their potential functional behavior can only be based on fine structure characterization. By combining advanced transmission electron microscopy, electron energy loss spectroscopy, density functional theory calculations, and multislice image simulations, we obtained evidence of a 7 nm-thick interface layer in LaSrMnO (LSMO) thin films, compatible with the formation of well-known dead layers in manganites, with an elongated out-of-plane lattice parameter and structural and electronic properties well distinguished from the bulk of the film. We observed, for the first time, a structural shift of Mn ions coupled with oxygen vacancies and a reduced Mn valence state within such layer.

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Persistent photoconductance is a phenomenon found in many semiconductors, by which light induces long-lived excitations in electronic states. Commonly, persistent photoexcitation leads to an increase of carriers (accumulation), though occasionally it can be negative (depletion). Here, we present the quantum well at the LaAlO_{3}/SrTiO_{3} interface, where in addition to photoinduced accumulation, a secondary photoexcitation enables carrier depletion.

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We investigate the effect of electric current pulse injection on domain walls in La(0.7)Sr(0.3)MnO(3) (LSMO) half-ring nanostructures by high resolution x-ray magnetic microscopy at room temperature.

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We study the effect of magnetocrystalline anisotropy on the magnetic configurations of La0.7Sr0.3MnO3 bar and triangle elements using photoemission electron microscopy imaging.

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SrRuO(3) is a strong itinerant ferromagnet showing many features of 'bad metals' together with Fermi liquid behavior at very low temperature. The intriguing magnetic and transport properties of SrRuO(3) are tightly related to structure, as commonly observed in transition metal oxides. Here we report on the correlation of structural parameters (lattice constant and surface roughness) with the critical behavior of resistivity at the Curie point in SrRuO(3) thin films deposited on (001) SrTiO(3) by PLD.

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Two kinds of epitaxial structures were grown by standard pulsed laser deposition on (001) Si, namely La(0.7)Sr(0.3)MnO(3)/Bi(4)Ti(3)O(12)/CeO(2) /YSZ/Si (BTO-based), and La(0.

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The experimental investigation of low-frequency noise properties in new materials is very useful for the understanding of the involved physical transport mechanisms. In this paper it is shown that, when contact noise is present, the experimental values of the normalized Hooge parameter show a fictitious linear dependence on the volume of the analyzed samples. Experimental data on noise measurements of La0.

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Electric noise measurements can give useful information on the conduction mechanisms and the dynamic behaviors of the charge carriers in new materials. However, it is well known that not all the electronic fluctuations are originated from the material itself, but some noise sources depend on the experimental procedures used for the measurements. In this article, an experimental technique to reduce "external" noise components, not associated with the bulk system, is presented.

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The role of membrane fatty acid composition in the resistance of Pseudomonas aeruginosa ATCC 15442 to the bactericidal activity of didecyldimethyl ammonium bromide (DDAB) was investigated. In this study, the strain was sub-cultured in a medium with increasing DDAB concentrations. After adaptation, Ps.

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