Orbital angular momentum states enabling fiber-based high-dimensional quantum communication

Quantum networks are the ultimate target in quantum communication, where many connected users can share information carried by quantum systems. The keystones of such structures are the reliable generation, transmission and manipulation of quantum states. Two-dimensional quantum states, qubits, are steadily adopted as information units. However, high-dimensional quantum states, qudits, constitute a richer resource for future quantum networks, exceeding the limitations imposed by the ubiquitous qubits. The generation and manipulation of such $D$-level systems have been improved over the last ten years, but their reliable transmission between remote locations remains the main challenge. Here, we show how a recent air-core fiber supporting orbital angular momentum (OAM) modes can be exploited to faithfully transmit $D$-dimensional states. Four OAM quantum states and their superpositions are created, propagated in a 1.2 km long fiber and detected with high fidelities. In addition, three quantum key distribution (QKD) protocols are implemented as concrete applications to assert the practicality of our results. This experiment enhances the distribution of high-dimensional quantum states, attesting the orbital angular momentum as vessel for the future quantum network

The Effect of the Pd Precursors on the Shape of Hollow Ag-Pd Alloy Nanoparticles Using Ag Nanocubes as Seeds

Hollow Ag-Pd nanoparticles have potentially highcatalyticperformance owing to their larger surface area compared to their correspondingsolid nanoparticles. We successfully fabricated hollow Ag-Pdalloy nanodendrites and nanoboxes by using different Pd precursors(H2PdCl4 and Pd(acac)(2)) to achievelarge surface area nanoboxes. Interestingly, the use of a H2PdCl4 precursor led to the formation of hollow nanodendritestructures, whereas the slower reduction of Pd(acac)(2) ledto the formation of hollow nanoboxes. The microstructure and chemicalcomposition of Ag-Pd nanoparticles and properties of theirgrowth solutions were investigated by transmission electron microscopy,energy-dispersive X-ray spectroscopy, and ultraviolet-visiblespectroscopy

Analisadores de práticas de apoio em humanização e educação permanente em saúde

Las Políticas Nacionales de Humanización y Educación Permanente en Salud han mostrado avances y retrocesos en su proceso histórico. Algunos conceptos del marco teórico del análisis institucional pueden contribuir a estos temas, como el concepto de analizador. El objetivo de este artículo fue discutir los analizadores identificados en una investigación-intervención, con profesionales que actúan como apoyadores de la humanización y/o articuladores de la educación permanente en salud en municipios de São Paulo. El marco teórico-metodológico fue el del análisis institucional, línea socioclínica, destacándose el trabajo de los analizadores. Participaron 30 personas en los grupos de intervención. Se destacan tres analizadores: (1) el analizador histórico Covid-19; (2) el analizador de tiempo; (3) el analizador de silencio. Estos analizadores iluminan tensiones como: el lugar periférico de la atención primaria, el malestar ante el “no saber” y/o el letargo ante el no hacer impuesto y la paradoja de crear e interrumpir tanto las acciones asistenciales como de apoyo a los equipos.The National Policies of Humanization and Permanent Health Education (PHE) have shown advances and setbacks in their historical process. Some concepts from the theoretical framework of institutional analysis can contribute in these themes, such as the concept of analyzer. This article discusses the analyzers identified in an intervention research with professionals who work as supporters of humanization and/or articulators of PHE in municipalities of the state of São Paulo. The theoretical-methodological framework is the institutional analysis, socio-clinical line, focusing on the work of the analyzers.As Políticas Nacionais de Humanização e Educação Permanente em Saúde têm mostrado em seu processo histórico avanços e retrocessos. Alguns conceitos do referencial teórico da análise institucional podem contribuir nesses temas, como o conceito de analisador. O objetivo do presente estudo foi discutir os analisadores identificados em uma pesquisa-intervenção, com profissionais que exercem a função de apoiadores de humanização e/ou de articuladores de educação permanente em saúde em municípios paulistas. O quadro teórico-metodológico é a análise institucional, linha sócio-clínica, sendo destacado, o trabalho dos analisadores. Participaram 30 pessoas dos grupos de intervenção. Destacamos três analisadores: (1) o analisador histórico Covid-19; (2) o analisador tempo; (3) o analisador silêncio. Esses analisadores iluminaram tensões como: o lugar periférico da atenção básica, o desconforto frente ao “não saber” e/ou a letargia ante o não-fazer imposto e o paradoxo de criar e interromper tanto ações de cuidado, como de suporte às equipes

Scalable WDM phase regeneration in a single phase-sensitive amplifier through optical time lenses

Scalable solutions for data regeneration of multiple parallel channels are elusive. Here the authors report a scalable wavelength-division multiplexing technique for phase regeneration and demonstrate the highest reported number of regenerated wavelength-division multiplexed channels in a single phase regenerator

The Spatial Extent and Distribution of Star Formation in 3D-HST Mergers at z~1.5

We present an analysis of the spatial distribution of star formation in a sample of 60 visually identified galaxy merger candidates at z>1. Our sample, drawn from the 3D-HST survey, is flux-limited and was selected to have high star formation rates based on fits of their broad-band, low spatial resolution spectral energy distributions. It includes plausible pre-merger (close pairs) and post-merger (single objects with tidal features) systems, with total stellar masses and star formation rates derived from multi-wavelength photometry. Here we use near-infrared slitless spectra from 3D-HST which produce Halpha or [OIII] emission line maps as proxies for star-formation maps. This provides a first comprehensive high-resolution, empirical picture of where star formation occurred in galaxy mergers at the epoch of peak cosmic star formation rate. We find that detectable star formation can occur in one or both galaxy centres, or in tidal tails. The most common case (58%) is that star formation is largely concentrated in a single, compact region, coincident with the centre of (one of) the merger components. No correlations between star formation morphology and redshift, total stellar mass, or star formation rate are found. A restricted set of hydrodynamical merger simulations between similarly massive and gas-rich objects implies that star formation should be detectable in both merger components, when the gas fractions of the individual components are the same. This suggests that z~1.5 mergers typically occur between galaxies whose gas fractions, masses, and/or star formation rates are distinctly different from one another.Comment: Accepted for publication in MNRAS, 16 pages, 10 figure