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Many-Body Dephasing by Hole Motion in a Spin-Orbit-Coupled Mott Insulator
No full textInternational audienceWe use Ramsey interferometry to study spin dynamics in the strongly interacting regime of spin-orbit-coupled quantum gases in one-dimensional optical lattices. We observe an intrinsic many-body dephasing mechanism immune to spin-echo in two-component Mott insulators. We ascribe the dephasing to the motion of hole-like defects in an otherwise inert Mott insulator, the spinless nature of the holes explaining the ineffectiveness of spin echo to restore it. We show that a model of spin-orbit-coupled hardcore bosons can explain quantitatively our experimental observations
The Foundations of an Ideal Dwelling in Japan in the Taishō Era. Between the Importance of the Environment and Reflection on Taste
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Modelling the water isotope distribution in the Mediterranean Sea using a high-resolution oceanic model (NEMO-MED12-watiso v1.0): evaluation of model results against in situ observations
No full textInternational audienceStable water isotopes (δ 18 O w and δD w ) have been successfully implemented for the first time in a high-resolution model of the Mediterranean Sea (NEMO-MED12). In this numerical study, model results are compared with available in situ observations to evaluate the model performance of the present-day distribution of stable water isotopes and their relationship with salinity on a subbasin scale. There is good agreement between the modelled and observed distributions of δ 18 O w in the surface water. The model successfully simulates the observed east-west gradient of δ 18 O w characterising surface, intermediate, and deep waters. The results also show good agreement between the simulated δD w and the in situ data. The δD w shows a strong linear relationship with δ 18 O w (r 2 = 0.98) and salinity (r 2 = 0.94) for the whole Mediterranean Sea. Moreover, the modelled relationships between δ 18 O w and salinity agree well with observations, with a weaker slope in the eastern basin than in the western basin. We investigate the relationship of the isotopic signature of the planktonic foraminifera shells (δ 18 O c ) with temperature and the influence of seasonality. Our results suggest a more quantitative use of δ 18 O records, combining reconstruction with modelling approaches
Thermodynamic properties of the macroscopically degenerate tetramer-dimer phase of the spin- Heisenberg model on the diamond-decorated square lattice
No full textInternational audienceThe spin-1/2 Heisenberg antiferromagnet on the diamond-decorated square lattice in the presence of a magnetic field displays various quantum phases including the Lieb-Mattis ferrimagnetic, dimer-tetramer, monomer-dimer, and spin-canted phases, in addition to the trivial fully saturated state. Thermodynamic properties of this model are investigated using several complementary analytical and numerical methods such as exact diagonalization up to the systems of 40 spins, an effective monomer-dimer description, sign-problem-free quantum Monte Carlo simulations for up to 180 spins, and a decoupling approximation. Our particular attention is focused on the parameter region favoring the dimer-tetramer phase. This ground state can be represented by a classical hard-dimer model on the square lattice and retains a macroscopic degeneracy even under a magnetic field. However, the description of the low-temperature thermodynamics close to the boundary between the macroscopically degenerate dimer-tetramer and the nondegenerate monomer-dimer phases requires an extended classical monomer-dimer lattice-gas model. Anomalous thermodynamic properties emerging in the vicinity of the dimer-tetramer phase are studied in detail. Under the adiabatic demagnetization we detect an enhanced magnetocaloric effect promoting an efficient cooling to absolute zero temperature
Le Vase des Trésors, Pratique de Prospérité des Ḍākinīs (mKha’ ‘gro ma’i nor sgrub gter gyi bum pa)
No full textMari und Aššur – in weiter Ferne, so nah!
No full textInternational audienceVeröffentlichung des bisher nur teilweise zitierten Briefes A.1248 aus Mari (Tell Hariri), in dem ein Autor behauptet, dass die beiden Städte Mari und Aššur nahe beieinander lägen. Der Briefverkehr zwischen beiden Städten war offensichtlich kein Problem für die Boten. Der Brief konnte mit Yasmah-Addu, dem jungen König von Mari identifiziert werden. Die Identifizierung der Adressatin, Akatiya, als Mutter Yasmah-Addus wird ausführlich diskutiert.Publication of letter A.1248 from Mari (Tell Hariri) formerly only quoted partially in which an author claims that the two cities, Mari and Aššur are close one to the other. The letter was written by Yasmah-Addu, the young king of Mari, to Akatiya. The identification of Akatiya with Yasmah-Addu's mother is discussed in detail.Publication de la lettre A.1248 de Mari (Tell Hariri), auparavant connue par des citations partielles. L'auteur affirme dans cette lettre que les deux villes, Mari et Aššur, seraient proches l'une de l'autre. La lettre a été écrite par Yasmah-Addu, le jeune roi de Mari, à Akatiya. L'identification d'Akatiya avec la mère de Yasmah-Addu est discutée en détail dans la contribution
Anthropogenic and biogenic pollutants in a forested environment: SPRUCE-22 campaign overview
No full textInternational audienceThe SPRUCE-22 field campaign was conducted during July 2022 on a remote mountainous forested site in Greece to assess interactions of biogenic and anthropogenic pollutants in the Eastern Mediterranean. Particle chemical composition and size distributions along with concentrations of organic and inorganic gases were measured at high temporal resolution, while samples were collected and analyzed off-line. PM1 1 had a surprisingly high average concentration of 13 mu g m-3 consisting primarily of organics (57%), followed by sulfate (30%), ammonium (9%), and black carbon (2%). Nitrates (both inorganic and organic) were less than 1% of the PM1 1 despite the relatively high NOx x emissions in the Balkans. The PM 2.5 concentrations at this remote site were similar and even higher than those in major cities across Greece including Athens, indicating the importance of regional transport for summertime pollution in the Eastern Mediterranean. The relatively constant average diurnal profiles of major anthropogenic pollutants are consistent with only minimal effects from local sources. Sulfates are not any more the dominant component of fine PM in Greece due to the reduction of SO2 2 emissions of coal-burning powerplants. The organic aerosol (OA) was quite oxidized with an average oxygen to carbon ratio (O:C) equal to 0.83. The average concentration of isoprene was 0.6 ppb, of monoterpenes 0.5 ppb, while the biogenic secondary organic aerosol factor (obtained through source apportionment analysis) was estimated to contribute 22% of the OA. Additional biogenic secondary organic aerosol (SOA) may be part of the two oxygenated OA (OOA) factors that were also identified. Radiocarbon analysis indicated that the non-fossil carbon was approximately equal to the sum of the biogenic and the more oxidized oxygenated OA, implying that the less oxidized OOA in this study was mostly associated to anthropogenic fossil fuel combustion. The biogenic SOA was quite aged (O:C equal to 0.63) and was also mostly transported to the site. Nearby new particle formation events occurred during 20 % of the days, with an average SO2 2 concentration of 0.3 ppb. The oxidative potential of the PM per unit of mass was quite high. The source attribution of the fine PM and the interactions among its anthropogenic and biogenic components are also discussed
Concepts and Antiquity. 2024 Chronicle - Barbarians in Ancient Civilizations 2: I- Introduction: Barbarians in Global Context (Anca Dan); II- Perception, Representation and Reception of Foreigners in Ancient Egypt (Shoufu Jin); III- Transformability between Self and Other in Ancient Greece and China (Yang Huang); IV- Barbarians in Early Byzantium (Randolph Ford)
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Individual Brain Charting dataset extension, third release for movie watching and retinotopy data
No full textInternational audienceThe Individual Brain Charting (IBC) is a multi-task functional Magnetic Resonance Imaging dataset acquired at high spatial-resolution and dedicated to the cognitive mapping of the human brain. It consists in the deep phenotyping of twelve individuals, covering a broad range of psychological domains suitable for functional-atlasing applications. Here, we present the inclusion of task data from both naturalistic stimuli and trial-based designs, to uncover structures of brain activation. We rely on the Fast Shared Response Model (FastSRM) to provide a data-driven solution for modelling naturalistic stimuli, typically containing many features. We show that data from left-out runs can be reconstructed using FastSRM, enabling the extraction of networks from the visual, auditory and language systems. We also present the topographic organization of the visual system through retinotopy. In total, six new tasks were added to IBC, wherein four trial-based retinotopic tasks contributed with a mapping of the visual field to the cortex. IBC is open access: source plus derivatives imaging data and meta-data are available in public repositories