Search

© 2014 American Physical Society. This work was supported by the Spanish Government through MAT2011-29269-C03, and NANOSELECT CSD2007-00041 projects and the Generalitat de Catalunya (2009 SGR 00376 project). J. G. acknowledges the Ramon y Cajal program (RYC-2012-11709). These experiments were performed at the Boreas beam line of the Synchrotron Light Facility ALBA with the collaboration of ALBA staff. Microscopy work was conducted in the STEM Group of the Oak Ridge National Laboratory (ORNL), and in the Laboratorio de Microscopías Avanzadas at the Instituto de Nanociencia de Aragón—Universidad de Zaragoza. Research at ORNL supported by the U.S. Department of Energy (DOE), Basic Energy Sciences (BES), Materials Sciences and Engineering Division (MV). Research atUCMsupported by the ERC Starting Investigator Award STEMOX 739239., Recent findings show the emergence of two-dimensional electron gases (2DEGs) at LaAIO_3/SrTiO_3 interfaces along different orientations; yet details on band reconstructions have remained so far unknown. Via x-ray linear dichroism spectroscopy, we demonstrate that crystal symmetry imposes distinctive 2DEG orbital hierarchies on (001)-and (110)-oriented quantum wells, allowing selective occupancy of states of different symmetry. Such orientational tuning expands the possibilities for electronic engineering of 2DEGs and opens up enticing opportunities to understand the link between orbital symmetry and complex correlated states at LaAIO_3/SrTiO_3 quantum wells., Spanish Government, Generalitat de Catalunya, Ramon y Cajal program, U.S. Department of Energy (DOE), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2014 AIP Publishing LLC. Financial support by the Spanish Government [Project Nos. MAT2011-29269-CO3 and NANOSELECT CSD2007- 00041] and Generalitat de Catalunya (No. 2009 SGR 00376) is acknowledged., We show that yttria-stabilized zirconia (YSZ) films deposited on structurally dissimilar SrTiO_(3)(110) substrates exhibit two-dimensional layer-by-layer growth. We observed that, up to a thickness of about 15 nm, the square (001) basal plane of the cubic YSZ grows epitaxially on the rectangular (110) crystallographic plane of SrTiO3 substrates, with [110]YSZ(001)//[001]SrTiO_(3)(110) epitaxial relationship. Thus, the heterointerface presents symmetry discontinuity between the YSZ(001) film and the lower surface symmetry SrTiO_(3)(110) substrate. Beyond this specific case, we envisage similar approaches to develop other innovative oxide interfaces showing similar crystal symmetry discontinuities., Ministerio de Economía y Competitividad (MINECO), Generalitat de Catalunya, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

Strain effects on epitaxial thin films of LaNiO3 grown on different single crystalline substrates are studied by Raman scattering and first-principles simulation. New Raman modes, not present in bulk or fully relaxed films, appear under both compressive and tensile strains indicating symmetry reductions. Interestingly, the Raman spectra and the underlying crystal symmetry for tensile and compressively strained films are different. Extensive mapping of LaNiO3 phase stability is addressed by simulations, showing that a variety of crystalline phases are indeed stabilized under strain. The calculated Raman frequencies reproduce the principal features of the experimental spectra, supporting the validity of the multiple strain-driven structural transitions predicted by the simulations.

Strain effects on epitaxial thin films of LaNiO3 grown on different single crystalline substrates are studied by Raman scattering and first-principles simulation. New Raman modes, not present in bulk or fully relaxed films, appear under both compressive and tensile strains indicating symmetry reductions. Interestingly, the Raman spectra and the underlying crystal symmetry for tensile and compressively strained films are different. Extensive mapping of LaNiO3 phase stability is addressed by simulations, showing that a variety of crystalline phases are indeed stabilized under strain. The calculated Raman frequencies reproduce the principal features of the experimental spectra, supporting the validity of the multiple strain-driven structural transitions predicted by the simulations.

IT WAS THE PURPOSE OF THIS STUDY TO DETERMINE WHETHER OR NOT PERSONALITY CHANGES RESULTING FROM BASIC TRAINING, AS REPORTED BY Ekman, Friesen and Lutzker, were stable over time or merely situational reactions to stress. Seventy ine of the original 92 subjects were retested with the MMPI at least six mo after the completion of basic training. Original test and retest data on these 79 men were analyzed with equivocal results. While some of the differences remained on retest and others did not, some new differences appeared. This leads one to wonder whether the changes reported in the earlier study are truly changes or if the groups differed to begin with. It should be emphasized that these alternatives are not mutually exclusive and that it is quit conceivable (in fact, probable) that both selection of subjec s and effects of basic training influenced the results. The original study, conceived as a pilot study, suggested some of the effects that basic training may have. T HE PRESENT STUDY, QUITE ACCIDENTALLY, POINTED OUT SOME OF THE INADEQUACIES OF THE FIRST. No conclusion can be drawn at the present time regarding the effects of basic training upon personality. A larger scale study controlli g more variables which may be relevant (e.g. religion, urban-rural residence, social class, etc.) seems to be needed. (Author)

The properties of the fibres of the stria terminalis have been analyzed on the basis of threshold, conduction velocity and absolute refractory period in anesthetized cats in which the stria terminalis was widely exposed. Both, fast and slow fibres, relay in the bed nucleus of the stria. Spontaneous unitary activity in the anterior and ventrome - dial hypothalamus had a predominant frequency of 6/sec., being both facilitated and inhibited by amygdaloid stimulation. Correlation of neuronal firing patterns, amygdaloid efferent pathways and location of units has been analized. (Author)