407 research outputs found
The Pharisees
We present here a study of Pharisaism with a view more fully to understand and appreciate the attitude of the Pharisees toward Jesus our Savior. The Scribes and the Pharisees were in a position of leadership in the church at the time of Christ\u27s visible sojourn here on earth. They had studied the Old Testament; they knew the Torah; and they were acquainted with the Messianic prophecies. But when the Messiah came in the person of Jesus Christ, the Pharisees were the men who turned out to be His most stubborn opponents. Why? There must have been some reason for it; and it is our aim to get at the heart of this matter
Autres contributions pour la connaissance de la végétation de la Hesse : pelouses acidiphile montagnardes et landes à dominance de nanophanérophytes
Pflanzengesellschaften der Borstgrasrasen und Zwergstrauch-Heiden (Calluno-Ulicetea) werden anhand von 27 Vegetationsaufnahmen beschrieben, die auf âPflanzensoziologischen Sonntagsexkursionenâ in den Jahren 1989 bis 1995 erstellt wurden. Der gröĂte Teil der Aufnahmen gehört zur Ordnung Nardetalia und reprĂ€sentiert BestĂ€nde des Festuco-Genistelletum sagittalis, des Juncetum squarrosi und einer Violion-Basalgesellschaft. Die dokumentierten Pflanzengesellschaften werden im Hinblick auf pflanzensoziologisch-syntaxonomische Aspekte, Ăkologie, Nutzung und GefĂ€hrdung charakterisiert.Nardus stricta grasslands and dwarf shrub heaths in Hesse are characterised with respect to their phytosociology, ecology, endangerment, and nature conservation on the basis of 27 relevĂ©s made between 1989 and 1995 during âphytosociological Sunday excursionsâ. The relevĂ©s mostly belong to the Festuco-Genistelletum sagittalis, Juncetum squarrosi, and a Violion basal community.Les communautĂ©s des nardaies et des fruticĂ©es naines Ă genĂȘt (Calluno-Ulicetea) ont Ă©tĂ© documentĂ©es grĂące aux 27 relevĂ©s faits lors des âPflanzensoziologische Sonntagsexkursionen (excursions phytosociologiques dominicales)â au cours des annĂ©es 1989 Ă 1995. La plupart des relevĂ©s appartiennent Ă lâordre Nardetalia et reprĂ©sentent les groupements des Festuco-Genistelletum sagittalis, des Juncetum squarrosi et dâune communautĂ© basale du Violion. Les communautĂ©s sont caractĂ©risĂ©es par rapport aux divers aspects suivants: sociologie, syntaxonomie, Ă©cologie, menace de disparition et conservation
Quantitative determination of bond order and lattice distortions in nickel oxide heterostructures by resonant x-ray scattering
We present a combined study of Ni -edge resonant x-ray scattering and
density functional calculations to probe and distinguish electronically driven
ordering and lattice distortions in nickelate heterostructures. We demonstrate
that due to the low crystal symmetry, contributions from structural distortions
can contribute significantly to the energy-dependent Bragg peak intensities of
a bond-ordered NdNiO reference film. For a LaNiO-LaAlO superlattice
that exhibits magnetic order, we establish a rigorous upper bound on the
bond-order parameter. We thus conclusively confirm predictions of a dominant
spin density wave order parameter in metallic nickelates with a
quasi-two-dimensional electronic structure
Tunable Charge and Spin Order in PrNiO Thin Films and Superlattices
We have used polarized Raman scattering to probe lattice vibrations and
charge ordering in 12 nm thick, epitaxially strained PrNiO films, and in
superlattices of PrNiO with the band-insulator PrAlO. A carefully
adjusted confocal geometry was used to eliminate the substrate contribution to
the Raman spectra. In films and superlattices under tensile strain, which
undergo a metal-insulator transition upon cooling, the Raman spectra reveal
phonon modes characteristic of charge ordering. These anomalous phonons do not
appear in compressively strained films, which remain metallic at all
temperatures. For superlattices under compressive strain, the Raman spectra
show no evidence of anomalous phonons indicative of charge ordering, while
complementary resonant x-ray scattering experiments reveal antiferromagnetic
order associated with a modest increase in resistivity upon cooling. This
confirms theoretical predictions of a spin density wave phase driven by spatial
confinement of the conduction electrons.Comment: PRL, in pres
Phase formation in hole- and electron-doped rare-earth nickelate single crystals
The recent discovery of superconductivity in hole-doped infinite-layer
nickelates has triggered a great interest in the synthesis of novel nickelate
phases, which have primarily been examined in thin film samples. Here, we
report the high-pressure optical floating zone (OFZ) growth of various
perovskite and perovskite-derived rare-earth nickelate single-crystals, and
investigate the effects of hole-, electron-, and self-doping. For hole-doping
with Ca and Sr, we observe phase separations during the growth process when a
substitution level of 8% is exceeded. A similar trend emerges for
electron-doping with Ce and Zr. Employing lower doping levels allows us to grow
sizeable crystals in the perovskite phase, which exhibit significantly
different electronic and magnetic properties than the undoped parent compounds,
such as a decreased resistivity and a suppressed magnetic response. Our
insights into the doping-dependent phase formation and the resulting properties
of the synthesized crystals reveal limitations and opportunities for the
exploration and manipulation of electronic states in rare-earth nickelates
Single crystal synthesis, structure, and magnetism of PbCu(PO)O
The recent claim of superconductivity above room temperature in
PbCu(PO)O with 0.9 < < 1 (referred to as LK-99) has
sparked considerable interest. To minimize the influence of structural defects
and impurity phases on the physical properties, we have synthesized phase-pure
single crystals with . We find that the crystals are highly
insulating and optically transparent. X-ray analysis reveals an uneven
distribution of the substituted Cu throughout the sample. Temperature ()
dependent magnetization measurements for K reveal the
diamagnetic response characteristic of a non-magnetic insulator, as well as a
small ferromagnetic component, possibly originating from frustrated exchange
interactions in Cu-rich clusters in the PbCu(PO)O
structure. No anomalies indicative of phase transitions are observed. We
therefore rule out the presence of superconductivity in PbCu(PO)O
crystals, and provide some considerations on the origin of anomalies previously
reported in experiments on polycrystalline specimen
Transfer of Magnetic Order and Anisotropy through Epitaxial Integration of 3d and 4f Spin Systems
Resonant x ray scattering at the Dy M 5 and Ni L 3 absorption edges was used to probe the temperature and magnetic field dependence of magnetic order in epitaxial LaNiO3 DyScO3 superlattices. For superlattices with 2 unit cell thick LaNiO3 layers, a commensurate spiral state develops in the Ni spin system below 100 K. Upon cooling below T ind 18 K, Dy Ni exchange interactions across the LaNiO3 DyScO3 interfaces induce collinear magnetic order of interfacial Dy moments as well as a reorientation of the Ni spins to a direction dictated by the strong magnetocrystalline anisotropy of Dy. This transition is reversible by an external magnetic field of 3 T. Tailored exchange interactions between rare earth and transition metal ions thus open up new perspectives for the manipulation of spin structures in metal oxide heterostructures and device
Three dimensional collective charge excitations in electron-doped cuprate superconductors
High temperature cuprate superconductors consist of stacked CuO2 planes, with
primarily two dimensional electronic band structures and magnetic excitations,
while superconducting coherence is three dimensional. This dichotomy highlights
the importance of out-of-plane charge dynamics, believed to be incoherent in
the normal state, yet lacking a comprehensive characterization in
energy-momentum space. Here, we use resonant inelastic x-ray scattering (RIXS)
with polarization analysis to uncover the pure charge character of a recently
discovered collective mode in electron-doped cuprates. This mode disperses
along both the in- and, importantly, out-of-plane directions, revealing its
three dimensional nature. The periodicity of the out-of-plane dispersion
corresponds to the CuO2 plane distance rather than the crystallographic c-axis
lattice constant, suggesting that the interplane Coulomb interaction drives the
coherent out-of-plane charge dynamics. The observed properties are hallmarks of
the long-sought acoustic plasmon, predicted for layered systems and argued to
play a substantial role in mediating high temperature superconductivity.Comment: This is the version of first submission. The revised manuscript
according to peer reviews is now accepted by Nature and will be published
online on 31st Oct., 201
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