1,720,994 research outputs found

    Silicon Carbide for Novel Quantum Technology Devices

    No full text
    Silicon carbide (SiC) has recently been investigated as an alternative material to host deep optically active defects suitable for optical and spin quantum bits. This material presents a unique opportunity to realise more advanced quantum-based devices and sensors than currently possible. We will summarise key results revealing the role that defects have played in enabling optical and spin quantum measurements in this material such as single photon emission and optical spin control. The great advantage of SiC lies in its existing and well-developed device processing protocols and the possibilities to integrate these defects in a straightforward manner. There is particular current interest in nanomaterials and nanophotonics in SiC that could, once realised, introduce a new platform for quantum nanophotonics and in general for photonics. We will summarise SiC nanostructures exhibiting optical emission due to multiple polytypic bandgap engineering and deep defects. The combination of nanostructures and in-built paramagnetic defects in SiC could pave the way for future single-particle and single-defect quantum devices and related biomedical sensors with single-molecule sensitivity. We will review relevant classical devices in SiC (photonics crystal cavities, microdiscs) integrated with intrinsic defects. Finally, we will provide an outlook on future sensors that could arise from the integration of paramagnetic defects in SiC nanostructures and devices

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

    Full text link
    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

    Full text link
    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

    No full text
    Nao informado

    Room temperature Single Photon Sources in Silicon Carbide

    No full text
    Defects are common in many materials and some were regarded for years as detrimental. Recently with the advent of ultra-sensitive detectors, quantum optical single spin magnetic resonance protocols and advanced material synthesis and doping, diamond intra-band gap defects and their nanostructured counterpart are revealed to be a disruptive discovery for the future of nanoscale sensing and quantum technologies[1]. We will report on recently studied optical centres in another wide-band gap semiconductor, such as silicon carbide (SiC). SiC harbors paramagnetic defects whose quantum properties were recently unraveled [2-7]. As occurred for similar diamond point defects[1], we have recently identified a bright single photon emission in 4H-SiC. We will show more recent results on single defects SiC nanoparticles [8], nanotetrapods [9] and other SiC quantum emission [10] providing novel information on their physics and atomistic structure. The fundamental understanding of these defects is essential for their engineering and deployment in next generation multifunctional sensors and in quantum nano- photonics. We will discuss the potential designs of photonics cavities to further enhance some of these single photon sources

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

    No full text
    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
    corecore