1,720,980 research outputs found
Cubic Dirac semimetals: General theory and application to rare-earth magnet
No full textRare-earth magnets with parent cubic symmetry exhibit unique topological properties. However, the origin of these behaviors presently remains unclear. Here, we develop minimal models for Dirac semimetals (DSMs) with accidental band crossings and higher-order topology in cubic systems, incorporating candidate magnetic order to analyze bulk, surface, and hinge state characteristics. In certain cubic-symmetric DSMs, we identify an effective ℤ2 chiral symmetry which significantly impacts surface and hinge-localized states. Our results highlight distinct features in surface-state dispersions, Fermi arcs, polarization dependence, and band splitting that correlate with photoemission data in rare-earth monopnictides. We also suggest candidate materials and experimental tests for further validation. These findings advance our understanding of surface states in rare-earth magnets with parent cubic symmetries and illuminate the role of DSM physics in these systems.This article is published Sur, Shouvik, and Chandan Setty. "Cubic Dirac semimetals: General theory and application to rare-earth magnets." Physical Review Research 7, no. 1 (2025): 013280.
doi: DOI: https://doi.org/10.1103/PhysRevResearch.7.013280
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
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
A Study of PEPS as Applied to Low Dimensional Quantum Magnets
Get PDFQuantum spin systems are particularly useful for the description of materials that exhibit magnetism. But, due to the quantum mechanical nature of such systems the problem size grows exponentially, quickly becoming intractable. Approximation schemes both analytical as well as numerical become useful at this point. However, there exist spin systems that are frustrated and remain beyond conventional treatments. In this project we use a numerical technique based on PEPS, to study quantum spin systems chiefly in 2-dimensions. The primary aim is to understand the behaviour of the algorithm, especially its limitations and why they exist. Such an investigation would be helpful in better implementation of the algorithm, as well as to improve upon its limitations via suitable approximation schemes.Master of Science (MS
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
Effective Field Theories for Metallic Quantum Critical Points
Get PDFIn this thesis we study the scaling properties of unconventional metals that arise at quantum
critical points using low-energy effective field theories. Due to high rate of scatterings between
electrons and critical fluctuations of the order parameter associated with spontaneous symmetry
breaking, Landau’s Fermi liquid theory breaks down at the critical points. The theories that
describe these critical points generally flow into strong coupling regimes at low energy in two
space dimensions. Here we develop and utilize renormalization group methods that are suitable
for the interacting non-Fermi liquids. We focus on the critical points arising at excitonic, and
commensurate spin and charge density wave transitions. By controlled analyses we find stable
non-Fermi liquid and marginal Fermi liquid states, and extract the scaling behaviour. The field
theories for the non-Fermi liquids are characterized by symmetry groups, local curvature of the
Fermi surface, the dispersion of the order parameter fluctuations, and dimensions of space and
Fermi surface.ThesisDoctor of Philosophy (PhD
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
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