Entanglement genesis by ancilla-based parity measurement in 2D circuit QED

We present an indirect two-qubit parity meter in planar circuit quantum electrodynamics, realized by discrete interaction with an ancilla and a subsequent projective ancilla measurement with a dedicated, dispersively coupled resonator. Quantum process tomography and successful entanglement by measurement demonstrate that the meter is intrinsically quantum non-demolition. Separate interaction and measurement steps allow commencing subsequent data qubit operations in parallel with ancilla measurement, offering time savings over continuous schemes.Comment: 5 pages, 4 figures; supplemental material with 5 figure

Zero kinetic energy-pulsed field ionization and resonance enhanced multiphoton ionization photoelectron spectroscopy: Ionization dynamics of Rydberg states in HBr

The results of rotationally resolved resonance enhanced multiphoton ionization photoelectron spectroscopy and zero kinetic energy‐pulsed field ionization studies on HBr via various rotational levels of the F^ 1Δ_2 and f^ 3Δ_2 Rydberg states are reported. These studies lead to an accurate determination of the lowest ionization threshold as 94 098.9±1 cm^(−1). Observed rotational and spin–orbit branching ratios are compared to the results of ab initio calculations. The differences between theory and experiment highlight the dominant role of rotational and spin–orbit interactions for the dynamic properties of the high‐n Rydberg states involved in the pulsed field ionization process

Biochemical evaluation of the nutrition status of urban school children of 12-15 years - riboflavin status

No Abstract

Direct microwave measurement of Andreev-bound-state dynamics in a proximitized semiconducting nanowire

The modern understanding of the Josephson effect in mesosopic devices derives from the physics of Andreev bound states, fermionic modes that are localized in a superconducting weak link. Recently, Josephson junctions constructed using semiconducting nanowires have led to the realization of superconducting qubits with gate-tunable Josephson energies. We have used a microwave circuit QED architecture to detect Andreev bound states in such a gate-tunable junction based on an aluminum-proximitized InAs nanowire. We demonstrate coherent manipulation of these bound states, and track the bound-state fermion parity in real time. Individual parity-switching events due to non-equilibrium quasiparticles are observed with a characteristic timescale $T_\mathrm{parity} = 160\pm 10~\mathrm{\mu s}$. The $T_\mathrm{parity}$ of a topological nanowire junction sets a lower bound on the bandwidth required for control of Majorana bound states

European Collaboration in Ocean Cores Science: roots, highlights, off-springs and vision

July 4th, 1947, exactly 75 years after the legendary cruise of H.M.S. Challenger and at a time when ocean science seemed to definitively shift to the shores of Massachusetts and California, the Swedish 5-masted schooner and school-ship Albatross set sail from Göteborg for a 15-months ambitious voyage of circumnavigation of the world oceans. Staffed with cadets and scientists and headed by Hans Pettersson, the Albatross had on board a revolutionary tool: Kullenberg’s piston corer, a 30m-long device which had already allowed the recovery of a 20m-long sediment core. Previously, the Meteor had recovered cores of a maximal length of 0.90m (1925), while in the thirties C.S. Piggot of the Carnegie Institution had “shot” cores up to 3m length in the North-Atlantic with a gun-like device. Sedimentological, geochemical, mineralogical, micropalaeontological analyses and radio-active dating would be carried out not only in Swedish institutes, but also in Vienna, Göttingen, Hanover, Wageningen, Ghent, Paris, London and La Jolla, in the true spirit of the data exploitation scheme which had shaped the success of the cruise of the Challenger. The stage was set for palaeo-environmental research on long sediment cores, archives of past climate and oceans.In the mid-sixties, ocean cores science takes a giant leap with the Deep Sea Drilling Program (DSDP). 20 years after the Albatross, in the fall of 1968, the Glomar Challenger sails from Dakar for the South Atlantic to verify the hypothesis of seafloor spreading and plate tectonics. Europe would join the Ocean Drilling Program (ODP), which set sail in 1984, subsequent to the International Phase of Ocean Drilling (IPOD, 1975-1983). For the first time, the European Science Foundation moves in, providing to numerous smaller European partners a platform of participation in ODP through ECOD, the European Consortium for Ocean Drilling.Some 50 years after the Albatross, the ‘Calypso’ piston corer on board of R/V Marion Dufresne would set the record of piston coring length, with an unrivaled core of over 64m length. The IMAGES programme would boost palaeoclimate research worldwide.At the turn of the century, ECORD - an off-spring of ECOD which had left the parental house - took the lead of the Mission Specific Platform (MSP) scheme in the Integrated Ocean Drilling Program (IODP), pushing frontiers of ocean drilling to extreme environments such as the poles and coral reefs. While not directly involved in the operational aspects, ESF soon took a prominent place in the supporting science, not the least through the EUROCORES programme and research networks.At the onset of the 21st century, while IODP and the international ocean drilling and coring community define a new strategy for post-2013 ocean coring science, Europe moves in with a new revolutionary tool, the MeBo (Meeresboden Bohrgerät), a remotely operated seabed drilling tool capable of drilling and coring from a variety of large vessels. EUROFLEETS provides new opportunities for coordinated naval operations for ocean science. And in parallel, Europe develops the plans for an ambitious drilling platform for the Arctic: Aurora Borealis.Any lucid vision on the future of Ocean Cores Science, which plays a key role in the unraveling of the dynamics of our planet, will build upon the lessons of the past, reflect upon the strengths and weaknesses of the present, and ride upon the excitement of Europe’s young generation, driver of the future

Probing dynamics of an electron-spin ensemble via a superconducting resonator

We study spin relaxation and diffusion in an electron-spin ensemble of nitrogen impurities in diamond at low temperature (0.25-1.2 K) and polarizing magnetic field (80-300 mT). Measurements exploit mode- and temperature-dependent coupling of hyperfine-split sub-ensembles to the resonator. Temperature-independent spin linewidth and relaxation time suggest that spin diffusion limits spin relaxation. Depolarization of one sub-ensemble by resonant pumping of another indicates fast cross-relaxation compared to spin diffusion, with implications on use of sub-ensembles as independent quantum memories.Comment: 5 pages, 5 figures, and Supplementary Information (2 figures

The High Frequency Instrument of Planck: Requirements and Design

The Planck satellite is a project of the European Space Agency based on a wide international collaboration, including United States and Canadian laboratories. It is dedicated to the measurement of the anisotropy of the Cosmic Microwave Background (CMB) with unprecedented sensitivity and angular resolution. The detectors of its High frequency Instrument (HFI) are bolometers cooled down to 100 mK. Their sensitivity will be limited by the photon noise of the CMB itself at low frequencies, and of the instrument background at high frequencies. The requirements on the measurement chain are directly related to the strategy of observation used for the satellite. Due to the scanning on the sky, time features of the measurement chain are directly transformed into angular features in the sky maps. This impacts the bolometer design as well as other elements: For example, the cooling system must present outstanding temperature stability, and the amplification chain must show, down to very low frequencies, a flat noise spectrum

Unraveling North-African riverine and eolian contributions to central Mediterranean sediments during Holocene sapropel S1 formation

Hydroclimate variability has exerted a fundamental control on the alternating deposition of organic-lean marl and organic-rich sapropel sediments in the eastern Mediterranean Sea (EMS). However, the exact mechanisms regarding the freshwater sources and related changes are still debated. Here, Sr and Nd isotopes and high-resolution elemental data are used to constrain different riverine and eolian supplies to the central Mediterranean over the past 9.8 ka. The detrital sediments in core CP10BC, taken at the margin of the Libyan shelf in the southwestern Ionian Sea, can be described by a three-endmember mixing system based on Sr and Nd isotopic compositions. The same systematics can also be deduced from Ti and K compositional variability. The endmembers comprise: Saharan Dust, Aegean/Nile, and Libyan Soil, representing the eolian supply from North Africa, the riverine inputs from the Aegean/Nile areas, as well as the riverine and shelf-derived fluxes from the Libyan-Tunisian margin, respectively. For the sapropel S1 period in particular, we find important detrital supplies from fossil river/wadi systems along the Libyan-Tunisian margin, activated by intensified African monsoon precipitation. Combining the temporal profiles with the consistent variability observed in the 87Sr/86Sr–1000/Sr diagram, such Libyan contribution has been most prominent during the uppermost period of sapropel S1 in core CP10BC. This observation is in agreement with hydroclimate reconstructions of northwestern Libya. Comparison of the Sr-Nd isotope data between core CP10BC and four cores taken along a west–east transect throughout the EMS shows that this detrital supply originated mainly from western Libya/Tunisia, and was transported as far eastward as ∼25°E while being diluted by an increasing Nile contribution

A hierarchy of linguistic predictions during natural language comprehension

Understanding spoken language requires transforming ambiguous acoustic streams into a hierarchy of representations, from phonemes to meaning. It has been suggested that the brain uses prediction to guide the interpretation of incoming input. However, the role of prediction in language processing remains disputed, with disagreement about both the ubiquity and representational nature of predictions. Here, we address both issues by analyzing brain recordings of participants listening to audiobooks, and using a deep neural network (GPT-2) to precisely quantify contextual predictions. First, we establish that brain responses to words are modulated by ubiquitous predictions. Next, we disentangle model-based predictions into distinct dimensions, revealing dissociable neural signatures of predictions about syntactic category (parts of speech), phonemes, and semantics. Finally, we show that high-level (word) predictions inform low-level (phoneme) predictions, supporting hierarchical predictive processing. Together, these results underscore the ubiquity of prediction in language processing, showing that the brain spontaneously predicts upcoming language at multiple levels of abstraction

Late Cenozoic diversification of the austral genus <i>Lagenophora</i> (Astereae, Asteraceae)

Lagenophora (Astereae, Asteraceae) has 14 species in New Zealand, Australia, Asia, southern South America, Gough Island and Tristan da Cunha. Phylogenetic relationships in Lagenophora were inferred using nuclear and plastid DNA regions. Reconstruction of spatio-temporal evolution was estimated using parsimony, Bayesian inference and likelihood methods, a Bayesian relaxed molecular clock and ancestral area and habitat reconstructions. Our results support a narrow taxonomic concept of Lagenophora including only a core group of species with one clade diversifying in New Zealand and another in South America. The split between the New Zealand and South American Lagenophora dates from 11.2Mya [6.1-17.4 95% highest posterior density (HPD)]. The inferred ancestral habitats were openings in beech forest and subalpine tussockland. The biogeographical analyses infer a complex ancestral area for Lagenophora involving New Zealand and southern South America. Thus, the estimated divergence times and biogeographical reconstructions provide circumstantial evidence that Antarctica may have served as a corridor for migration until the expansion of the continental ice during the late Cenozoic. The extant distribution of Lagenophora reflects a complex history that could also have involved direct long-distance dispersal across southern oceans.Facultad de Ciencias Naturales y MuseoInstituto de Limnología "Dr. Raúl A. Ringuelet