1,721,065 research outputs found
Ultra-high-Q chalcogenide glass on-chip resonators attaining internal impurity-limited loss in the mid-infrared
No full textHigh-Q on-chip resonators are essential for elevating the efficiency and performance of on-chip functional devices. However, achieving their loss performance that approaches the ultra-low loss of optical fiber in the mid-infrared region has remained a challenge. Here, we demonstrate ultra-high-Q mid-infrared on-chip microresonators based on multiple chalcogenide glasses, exhibiting optical loss characteristics comparable to those of state-of-the-art optical fibers. By suppressing optical losses from scattering and molecular absorption, Q-factors exceeding 10 million were achieved across the 3.2 to 4.6 mu m range, peaking at 67 million (0.29 dB/m) at 3.91 mu m. The loss performance of these resonators is fundamentally limited by the intrinsic material losses, as good agreement with the optical loss spectrum of ChG fibers. In addition, the absence of absorption peaks induced by Se-H in the As2Se3 core layer is consistent with the spectral characteristics of Se-H-free fibers, indicating that the deposited film retained the purity of its evaporation source. This result underscores the importance of mitigating internal impurities at the chip scale to achieve low optical loss in the mid-infrared.
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Novel tuned phosphate systems and glass fabrication for various optical applications
No full textPhosphate glass systems containing P2O5: TeO2: BaF2: ZnO: LiCl and Nb2O5: CdO: Ag2O with transition metal oxides NiO: CuO: MnO2 and dopant ions of La2O3: Tm2O3: Eu2O3 have been fabricated. The thermal, optical, and luminescence properties of the present glasses were investigated. The prepared glasses have been fabricated with high-quality, and some of these glasses have application in bandpass filters in the UV and VIS region (especially red), and also glasses doped with rare earth ions have potentials to use in solid lasers, optical amplifiers, and optical coherence tomography (OCT). The produced glasses have low OH, homogenous, and the luminescence performance is good. The produced glasses co-doped with Tm2O3/Eu2O3 led to the broadening of the optical telecommunication band for NIR photoluminescence emission. Moreover, the synthesized glasses doped with Mn2O3/Ag2O/Pr2O3, Eu2O3/Tm2O3 are superior materials for wideband near-infrared phosphors and candidates for LED-based light sources and optical fiber applications between 0.45 and 1.84 µm
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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