Abstract Polycrystalline Pr 2 NiO 4+δ coatings have been deposited on alumina substrates at room ... more Abstract Polycrystalline Pr 2 NiO 4+δ coatings have been deposited on alumina substrates at room temperature by RF magnetron co-sputtering from Pr and Ni metallic composite target. The mixed target's area and the sputtering conditions were optimized to reach an atomic ratio Pr/Ni of 2. A subsequent annealing, at 1050–1100 °C, allowed obtaining Pr 2 NiO 4+δ phase after in situ high temperature x-ray diffraction study performed on as-deposited film. Microstructural analyses (SEM and AFM) revealed dense and rough microstructure. Normal spectral emittance measurements performed at 794 °C in the spectral range 400–5000 cm -1 showed an emissivity of e ≈ 0.8.
ABSTRACT Samples of copper-deficient CaCu3Ti4O12 (CCTO) compared to the nominal composition, all ... more ABSTRACT Samples of copper-deficient CaCu3Ti4O12 (CCTO) compared to the nominal composition, all synthesized via organic gel-assisted citrate process, show huge change of grain boundaries capacitance as deduced from a fit of a RC element model to the impedance spectroscopic data. The grain boundary capacitance is found to scale with the permittivity measured at 1 kHz weighted by the size of the grains. This result is found consistent with the internal barrier layer capacitance (IBLC) model.
Phase separation has been recognized as an important ingredient to create the colossal magnetores... more Phase separation has been recognized as an important ingredient to create the colossal magnetoresistance (CMR). To be able to characterize the phase separation signature by electron spin resonance (ESR), a preliminary work has been undertaken in order to check typical ESR behaviours of prototype manganites. These behaviours are antiferromagnetism (A-type, CE-type), charge order, ferromagnetism and phase separation. Five compounds were
For electronic devices, good ohmic contacts are required. To achieve such contacts, the semicondu... more For electronic devices, good ohmic contacts are required. To achieve such contacts, the semiconductor layer has to be highly doped. The only method available to locally dope the SiC is to implant dopants in the epilayer through a mask. In this work, non-intentionally doped 3C–SiC epilayers were implanted using nitrogen or phosphorus at different energies and subsequently annealed at temperatures
Abstract Polycrystalline Pr 2 NiO 4+δ coatings have been deposited on alumina substrates at room ... more Abstract Polycrystalline Pr 2 NiO 4+δ coatings have been deposited on alumina substrates at room temperature by RF magnetron co-sputtering from Pr and Ni metallic composite target. The mixed target's area and the sputtering conditions were optimized to reach an atomic ratio Pr/Ni of 2. A subsequent annealing, at 1050–1100 °C, allowed obtaining Pr 2 NiO 4+δ phase after in situ high temperature x-ray diffraction study performed on as-deposited film. Microstructural analyses (SEM and AFM) revealed dense and rough microstructure. Normal spectral emittance measurements performed at 794 °C in the spectral range 400–5000 cm -1 showed an emissivity of e ≈ 0.8.
ABSTRACT Samples of copper-deficient CaCu3Ti4O12 (CCTO) compared to the nominal composition, all ... more ABSTRACT Samples of copper-deficient CaCu3Ti4O12 (CCTO) compared to the nominal composition, all synthesized via organic gel-assisted citrate process, show huge change of grain boundaries capacitance as deduced from a fit of a RC element model to the impedance spectroscopic data. The grain boundary capacitance is found to scale with the permittivity measured at 1 kHz weighted by the size of the grains. This result is found consistent with the internal barrier layer capacitance (IBLC) model.
Phase separation has been recognized as an important ingredient to create the colossal magnetores... more Phase separation has been recognized as an important ingredient to create the colossal magnetoresistance (CMR). To be able to characterize the phase separation signature by electron spin resonance (ESR), a preliminary work has been undertaken in order to check typical ESR behaviours of prototype manganites. These behaviours are antiferromagnetism (A-type, CE-type), charge order, ferromagnetism and phase separation. Five compounds were
For electronic devices, good ohmic contacts are required. To achieve such contacts, the semicondu... more For electronic devices, good ohmic contacts are required. To achieve such contacts, the semiconductor layer has to be highly doped. The only method available to locally dope the SiC is to implant dopants in the epilayer through a mask. In this work, non-intentionally doped 3C–SiC epilayers were implanted using nitrogen or phosphorus at different energies and subsequently annealed at temperatures
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