The landscape of academic literature in quantum technologies

In this study, we investigated the academic literature on quantum technologies (QT) using bibliometric tools. We used a set of 49,823 articles obtained from the Web of Science (WoS) database using a search query constructed through expert opinion. Analysis of this revealed that QT is deeply rooted in physics, and the majority of the articles are published in physics journals. Keyword analysis revealed that the literature could be clustered into three distinct sets, which are (i) quantum communication/cryptography, (ii) quantum computation, and (iii) physical realizations of quantum systems. We performed a burst analysis that showed the emergence and fading away of certain key concepts in the literature. This is followed by co-citation analysis on the “highly cited” articles provided by the WoS, using these we devised a set of core corpus of 34 publications. Comparing the most highly cited articles in this set with respect to the initial set we found that there is a clear difference in most cited subjects. Finally, we performed co-citation analyses on country and organization levels to find the central nodes in the literature. Overall, the analyses of the datasets allowed us to cluster the literature into three distinct sets, construct the core corpus of the academic literature in QT, and to identify the key players on country and organization levels, thus offering insight into the current state of the field. Search queries and access to figures are provided in the appendix.

Citations driven by social connections? A multi-layer representation of coauthorship networks

To what extent is the citation rate of new papers influenced by the past social relations of their authors? To answer this question, we present a data-driven analysis of nine different physics journals. Our analysis is based on a two-layer network representation constructed from two large-scale data sets, INSPIREHEP and APS. The social layer contains authors as nodes and coauthorship relations as links. This allows us to quantify the social relations of each author, prior to the publication of a new paper. The publication layer contains papers as nodes and citations between papers as links. This layer allows us to quantify scientific attention as measured by the change of the citation rate over time. We particularly study how this change correlates with the social relations of their authors, prior to publication. We find that on average the maximum value of the citation rate is reached sooner for authors who have either published more papers or who have had more coauthors in previous papers. We also find that for these authors the decay in the citation rate is faster, meaning that their papers are forgotten sooner.

Uncovering diffusion trends in computer science and physics publications

Purpose The purpose of this paper is to trace the knowledge diffusion patterns between the publications of top journals of computer science and physics to uncover the knowledge diffusion trends. Design/methodology/approach The degree of information flow between the disciplines is a measure of entropy and received citations. The entropy gives the uncertainty in the citation distribution of a journal; the more a journal is involved in spreading information or affected by other journals, its entropy increases. The citations from outside category give the degree of inter-disciplinarity index as the percentage of references made to papers of another discipline. In this study, the topic-related diffusion across computer science and physics scholarly communication network is studied to examine how the same research topic is studied and shared across disciplines. Findings For three indicators, Shannon entropy, citations outside category (COC) and research keywords, a global view of information flow at the journal level between both disciplines is obtained. It is observed that computer science mostly cites knowledge published in physics journals as compared to physics journals that cite knowledge within the field. Originality/value To the best of the authors’ knowledge, this is the first study that traces knowledge diffusion trends between computer science and physics publications at journal level using entropy, COC and research keywords.

Astrophysical dynamos: the limit of vanishing diffusivity

Astrophysical dynamos are usually characterised by huge values of the magnetic Reynolds number (Rm). This reflects the short turn-over time compared to the resistive time. The extreme values of Rm relevant to astrophysical objects cannot be tackled with today's numerical resources and this number is always under-estimated by several orders of magnitudes in numerical models.Here we chose to focus on an extremely simplified problem (dynamo action from a periodic steady flow) and take advantage of this simplicity to numerically investigate the limit of very large magnetic Reynolds number. We present results recently published in physics journals, which highlight the difficulty of approaching the limit in which dynamo action is independent of the value of the ohmic resistivity (measured by 1/Rm), known as the “fast dynamo” limit. Using state of the art high performance computing, we present high resolution simulations (up to (40963) and extend the value of (Rm) up to (5⋅105).