186,159 research outputs found
Mie-resonant mesoporous electron transport layer for highly efficient perovskite solar cells
All-dielectric nanophotonics is a powerful tool for improvement of thin-film optoelectronic devices because of low optical losses, strong light localization, and chemical robustness against such materials as halide perovskites. However, large-scale and low-cost approaches to create functional nanostructures are still not developed. In our work, we show a novel method to create mesoporous electron transport layer based on optically resonant silicon nanoparticles incorporated into TiO2 paste to be applied for perovskite (MAPbI(3)) solar cell. The inclusion of Mie-resonant silicon nanoparticles helps to improve light absorption by a perovskite layer without reduction of the active material. The management of Si nanoantennas concentration provides to reach a power conversion efficiency higher than 21% by increasing all main device parameters. Our multi-physical theoretical simulations of the solar cells with the resonant silicon nanoparticles provide physical understanding on the mechanisms of the device improvement as well as help to optimize the silicon nanoparticles concentration
Author-wise bibliometric analysis based on entropy.
Author-wise bibliometric analysis based on entropy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
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
Appropriate Similarity Measures for Author Cocitation Analysis
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
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
Dr. Edward P. Wimberly, ITC, July 2011
This video is a conversation with Dr. Edward P. Wimberly. Dr. Wimberly talks about his book, "No Shame in Wesley's Gospel: A Twenty-First Century Pastoral Gospel". Brad Ost, AUC Woodruff Library, is the interviewer
Author Rights and Scholarly Publishing
Originally posted at
http://blog.library.gsu.edu/2014/10/24/author-rights-and-scholarly-publishing/</p
Enhanced Five-Photon Photoluminescence in Subwavelength AlGaAs Resonators
Multiphoton processes of absorption photoluminescence have enabled a wide range of applications including three-dimensional microfabrication, data storage, and biological imaging. While the applications of two-photon and three-photon absorption and luminescence have matured considerably, higher-order photoluminescence processes remain more challenging to study due to their lower efficiency, particularly in subwavelength systems. Here, we report the observation of five-photon luminescence from a single subwavelength nanoantenna at room temperature enabled by the Mie resonances. We excite an AlGaAs resonator at around 3.6 μm and observe photoluminescence at around 740 nm. We show that the interplay of the Mie multipolar modes at the subwavelength scale can enhance the efficiency of the five-photon luminescence by at least 4 orders of magnitude, being limited only by sensitivity of our detector. Our work paves the way toward applications of higher-order multiphoton processes at the subwavelength scales enabled by the physics of Mie resonances
Observation of Giant Five-Photon Upconversion Luminescence in Subwavelength AlGaAs Resonators
We design and fabricate individual subwavelength AlGaAs nanoantennas supporting Mie resonances in the mid-infrared spectral range. Near the resonant modes, we observe five-photon upconversion photoluminescence in the visible spectral range
- …
