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Single-phase electron-doped manganite thin films with nominal composition of La0.7Ce0.3MnO3 (LCeMO) have been prepared on SrTiO3 (100) substrates by pulsed laser deposition. The conditions for obtaining purely single-phase LCeMO films lie within a very narrow window of substrate temperature (Ts∼720 °C) and laser energy density (ED∼2 J/cm2) during deposition. In situ postdeposition annealing, mainly to relax the possible epitaxial in-plane tensile strain between the film and the substrate, leads to an increasing c-axis lattice constant accompanied by the formation of secondary CeO2 phase and higher metal-insulator transition temperature. This is indicative of a strong coupling between the electron and lattice degree of freedom. [ABSTRACT FROM AUTHOR]

The electron energy-loss magnetic chiral dichroism (EMCD) technique has been generally applied to single-phase magnetic crystals while rarely used for composite structures. It is mainly due to the lack of in-depth understanding of EMCD in the latter case where an additional phase may present under or above the investigated magnetic phase in the electron beam path. Here, we report EMCD signals acquired on a 15-nm-thick magnetic iron film with different thicknesses of the MgO substrate underlayer. By comparison, for areas with total thicknesses of t = 0.59 λ and t = 1.02 λ expressed with the mean free inelastic path of electron λ , the relative dichroic signals at the Fe ‐ L 3 edge are 3.8 % ± 1.0 % and 3.5 % ± 1.6 % , respectively, demonstrating no significant difference within the error range. However, the dichroic signal intensity at the Fe ‐ L 2 edge peak is 77.6% larger in the thinner area of t = 0.59 λ. Accordingly, the extracted m L / m s ratio of Fe 3 d moments is 63% smaller in the thinner area even after the plural scattering is removed. Then, we confirm that the presence of an additional nonmagnetic phase under a magnetic iron crystal can noticeably affect the quantified value of the m L / m s ratio of iron moment determined from the EMCD measurements. Furthermore, the larger thickness of the underlayer may result in relatively higher valuation of the m L / m s ratio of the upper layer. A correction method, considering the different influence of the underlayer on the Fe ‐ L 3 and L 2 edges, is in demand for developing potential applications of the EMCD technique to such composite nanomaterial systems. [ABSTRACT FROM AUTHOR]

Deals with a study which investigated submicron indium phosphide transferred electron devices. Method used to model the direct current characteristics of near-micron structures; Background on the physical origins of the length effect in submicron structures; Description of the static characteristics of transferred electron devices.