Quantum Sensing Research: A Scientometric Assessment of Global Publications during 1991-2020

1. Introduction

Quantum sensing deals with quantum measurement, exploring the use of quantum properties in single particles to measure a broad range of physical quantities, and to set higher levels of measurement accuracy, far beyond what was the limit previously perceived by uncertainty principle (Degen, Reinhard & Cappellaro, 2017). Quantum sensing uses quantum technologies to design and engineer drastically improved sensors and measuring devices (Pirandola et al., 2018). Quantum sensors promise far more accuracy in measurements than conventional sensors. Quantum sensors promise new detection capabilities, detecting even the tiniest electrical signals in the human body, monitoring brain activity on the go, and detecting underground signals that will have applications in civil engineering and resource extraction including oil and gas. It will now be possible to have ultra-accurate navigation, even underwater, and sense changes in gravity thereby revealing potential earthquakes or volcanic activity, climate change. Above all, it will be possible to measure physical quantities against atomic properties, so there is no drift or need to calibrate (CNRS, 2021; NATO, 2020; Tetienne & Hall, 2021). In brief, quantum sensing finds innovative applications in as diverse fields as metrological standards, biological imaging, navigation systems, detailed underground mapping, next generation detectors, and autonomous cars (Fuentes & Bouyer, 2021). Quantum sensing not only have important commercial applications, they have potential to improve our everyday life and will also deepen our understanding of nature. Given the disruptive role that quantum sensing technologies are going to play in the near future, it will be worthwhile that a bibliometric study be undertaken to analyze and evaluate the global literature in quantum science research with the aim to identify the key players in this research at global, national, institutional, and individual scientist level.

2. Literature Review

As seen from the literature, no bibliometric study has been published till date on the topic assessment and evaluation of national and global research on quantum sensing. However, quite a few studies on similar topics have already been undertaken, such as quantum technologies, quantum computing (4703 global publications during 2007-16) quantum machine learning (1374 global publications during 1999-20), quantum neural networks (546 global records during 1990-19), quantum cryptography (10801 publications during 1992-20), quantum electronics (10115 records since 2008), quantum information processing (2000-17), quantum robotics (650 global records during 1993-20) and quantum dots (Dhawan, Gupta & Mamdapur, 2018; Dhawan, Gupta & Mamdapur, 2021; Gupta & Dhawan, 2020a; Dhawan, Gupta & Mamdapur, 2021; Ibrahim, Julius & Choudhury, 2021; Terekhov, 2020; Gupta & Dhawan, 2020b; Gupta, Dhawan & Mamdapur, 2021; Seskir & Aydinoglu, 2021; Tolcheev, 2018). Given the fact that no study has been undertaken till date in quantum sensing, the authors thought it appropriate to fill the gap and accordingly undertake this study to assess and evaluate global literature in the subject on metrics.

3. Objectives

The study seeks to understand the status and performance of global research in the domain of quantum sensing at global, national, institutional, and individual author level based on select indicators derived from publications and citation data in the subject. The data for the study has been sourced from the Scopus international database for the period 1991-2020. For research evaluation, the publications data on quantum sensing will be analyzed on a number of parameters (i) distribution of publications by type and source, (ii) publication growth rate- annual and cumulative, (iii) quantify citation impact of publications in terms of citations per paper, relative citation index, and share of highly-cited papers (iv) identify the most productive countries in the world, (v) distribution of publications by broad subjects and significant keywords, (vi) identify and profile of most productive organizations and the most productive authors in the world, (vii) identify top channels for research communication, and (viii) describe the bibliographic characteristics of highly-cited papers in the subject.

4. Methodology

The Scopus database (https://www.scopus.com) is used in this study for sourcing publication and citation data on the topic of quantum sensing research. A comprehensive search strategy was developed for identifying, retrieving, and downloading publications metadata. The keywords “quantum sensing” and “quantum sensors” were clubbed to field tags “Keyword” and “Title” (Article Title). The search output was confined to global search limited to the publication period ‘1991-20’. Subsequently, the search output was refined by the publication country name, one by one, to identify and generate a list of top 10 most productive countries of the world in this subject. The search yielded 588 global records, which were downloaded in csv file format to be further analyzed using statistical methods. The analytical provisions of the Scopus database were used to generate statistics on the publications output by broad subject areas, collaborating countries, contributing authors, affiliating organizations, and source journals, etc. The citations to each publication were counted from the date of their publication till 27.2.2021. The study examined the performance of the most productive countries, organizations, authors and journals on select bibliometric indicators. The VOS viewer and biblioshiny app for bibliometrix were used to evaluate and visualize the interactions among most productive countries/territories, organizations, authors and keywords. (TITLE (“quantum sensor*” or “quantum sensing”) OR KEY (“quantum sensor*” or “quantum sensing”)) AND (EXCLUDE (PUBYEAR, 2021)).

5. Analysis and Results

5.1 Publication and Citation Analysis

The global research in the domain of quantum sensing accumulated a total of 588 publications, an average of 19.6 publications per year during 1991-2020. The research in the subject: (i) registered a 14.85% annual average growth, (ii) its annual output increased in publication volume from just 1 to 121 during 1991-2020 and (iii) its 15-year cumulative output increased by 16.37.5% from 32 in 1991-05 to 556 in 2006-20. Of the total output, the largest share appeared as articles and conference papers (55.27% and 35.54%), respectively. The remaining output appeared as reviews (3.74%), conference reviews (2.55%), book chapters (1.19%), letters and short surveys (0.51% each) and book, editorial, note and erratum (0.17% each). The quantum sensing research registered a citation impact of 12.04 citations per paper (CPP) since publication during 1991-2020. Its citation impact in a 15 year window since publication was the highest, at 18.63 CPP in 1991-2005, which slipped to 11.66 CPP in 2006-2020 (Table 1).

Table 1.

Quantum sensing research: global publications output and citations 1991-2020

Of the total 588 publications, 253 (43.03%) had resulted from sponsored research projects funded by 100+ national and international funding agencies. The number of funded papers increased in publication volume from 3 in 1991-2005 to 250 in 2006-20. The bulk of the funded papers, 73.52% share, appeared during the last 3 years.

The sponsored research papers received a total of 3640 citations since their publication, registering a citation impact of 14.39 citations per paper, marginally above the world average of 12.04 CPP. The leading funding agencies in quantum sensing research were: National Science Foundation (45 papers), European Research Council (32 papers), Deutsche Forschungsgemeinschaft and European Commission (24 papers each), Horizon 2020 Framework Program (21 papers), National Natural Science Foundation of China (20 papers), Japanese Society for Promotion of Science (18 papers), etc.

5.2 Top 10 most productive countries

The global research in the domain of quantum sensing witnessed the participation of 48 countries across the world. The distribution of research by country of publication is skewed: 31 countries contributed 1-10 papers each, 14 countries 11-50 papers each and 2 countries 108-206 papers each. The USA and Germany lead the global ranking with 35.03% and 18.37% global share respectively, followed by the U.K., China, Italy, Japan, France and Australia (from 5.27% to 9.86%), Russia Federation and Switzerland (4.76% and 3.91%). Five of the top 10 countries registered their relative citation index above the group average (1.23): Switzerland (6.02), Australia (1.46), U.K. (1.41), USA (1.39) and Germany (1.27). The international collaborative papers (ICP) as a share of national output of top 10 countries varied from 27.18% to 72.41%, with an average of 47.62% (Table 2).

Table 2.

Quantum sensing research: top 10 most productive countries 1991-2020

5.2.1 Collaborative linkages among top 10 countries

All of the top 10 most productive countries collaborated in quantum sensing research; their one-to-many collaborative linkages count varied from 17 to 330. Their one-to-one collaborative linkages, between two countries constitute a total of 441 linkages and these varied from 14 to 108. Germany, the USA and the U.K. registered the largest number of collaborative linkages (108, 73 and 70) with other countries. Similarly, Russia Federation, Switzerland and China registered the lowest number of collaborative linkages (14, 21 and 25) with other countries. Among the leading country-to-country collaborations, the Germany-France topped the list, registered the highest number of collaborative linkages (14), followed by the USA-Germany (13 linkages), Germany-U.K. (12 linkages), USA-U.K. (9 linkages), Germany-China (7 linkages), USA-Italy, Germany-Italy, Germany-Japan, Germany-Switzerland, U.K.-France, U.K.-Australia and Italy-France (6 linkages each), etc (Table 3). A total 47 countries were engaged in Quantum Sensing research. A visual map network interactions among top ten countries was created using VOS viewer tool. The collaborative linkages for Germany were the maximum 71 (9 nodes), followed by the USA 47 (9 nodes) and the U.K. 43 (8 nodes). These top 10 collaborating countries appear in two clusters as shown in Fig. 1. The thickness of links between the countries coupled with the distance between them represents the degree of their collaboration in research. The bigger the diameter of a network country node and its font size, the bigger its weight in research collaboration.

Table 3.

Quantum sensing research: collaborative linkages among most productive countries 1991-2020

Fig. 1.

Country-wise collaboration network visualization

5.3 Subject-wise distribution

The Scopus database classified the global output on the topic of quantum sensing in 7 broad disciplines (Table 3). Physics & Astronomy, Engineering and Materials Science are the top subject areas intersecting with quantum sensing research. They accounted for 76.02%, 45.07% and 42.52% for global share respectively in the subject, followed by Computer Science and Mathematics (21.43% and 17.18%), Chemistry and Biochemistry, Genetics & Microbiology (8.67% and 7.65%) during 1992-2020. In terms of research activity index between 1991-2005 and 2006-2020, the subjects which showed a jump in their research activity in 11 years were: Physics & Astronomy, Engineering Materials Science, Chemistry and Biochemistry, Genetics & Microbiology. Besides, Computer Science and Mathematics showed a decline in research activity during the period. Of the top ten subjects, Chemistry registered the highest citation impact per paper (25.9 CPP) and Biochemistry, Genetics & Molecular Biology subject the lowest (1.48 CPP) (Table 4).

Table 4.

Quantum sensing research: subject-wise breakup of global publications 1999-2020

5.3.1 Significant keywords

The top 43 keywords (assumed to be significant) were identified from the global literature (588) on quantum sensing research (Table 4). These keywords, considered as research hot-spots, provide a secondary approach to identify research trends in the domain of quantum sensing. The frequency of keyword occurrence in the quantum sensing literature for 1991-2020 was the maximum (250) for ‘Quantum Sensors’, followed by ‘Quantum Sensing’ (132), ‘Quantum Optics’ (110), ‘Quantum Theory’ (90), ‘Quantum Entanglement’ (81), ‘Photons’ (62), ‘Nitrogen Vacancy Center’ (55), ‘Nitrogen Vacancies’ (51), etc (Table 5). A co-occurrence relationship chart of top keywords is shown in Fig. 2. The size of each node (associated to a keyword) is proportional to the number of documents where the keyword appears. Keywords co-occurrence chart created using VOS viewer software formed four clusters. Red and green colour clusters with 15 items each, blue colour with 11 items and yellow colour with 2 items as shown in Fig. 2.

Table 5.

List of top 43 significant keywords appearing in global quantum sensing literature

Fig. 2.

Keywords Co-occurrence Networks chart on Quantum Sensing research from 1991 to 2020.

5.4 Top 15 most productive organizations

In all, a total of 293 organizations were found to have participated in quantum sensing research during 1991-2020. Of these, 231 organizations published 1-5 papers each, 40 organizations 6-10 papers each, 18 organizations 11-20 papers each and 5 organizations 21-36 papers each. Of the top 15 most productive global organizations in quantum sensing research, 4 each were from the USA, Germany and Italy and 3 from France. The research productivity of top 15 most productive organizations in the subject varied from 12 to 36 publications per organization; together they contributed a 35.52% (488) global publications share and a 76.62% (17190) global citations share during the period. The scientometric profile of top 15 most productive organizations is presented in (Table 6). On further analysis, it was observed that (i) Five of the 15 organizations contributed publications above average productivity (18.13) of all 15 organizations: Naval Research Lab., USA (36 papers), Massachusetts Institute of Technology, USA (34 papers), University of Ulm, Germany (30 papers), Gottfried Wilhelm Leibniz Universitat Hannover, Germany (27 papers) and Humboldt-Universitat zu Berlin, Germany (21 papers); and (ii) Two of the top 15 organizations performed, in terms of citation per paper and relative citation index, above their group average (12.82 and 1.06 respectively): Massachusetts Institute of Technology, USA (38.76 and 3.22) and University of Ulm, Germany (19.4 and 1.61).

Table 6.

Scientometric profile of 15 most productive organizations in quantum sensing research 1991-2020

5.4.1 Institutional collaboration linkages among top 15 organizations

The top 15 most productive organizations collaborated in quantum sensing research. Their combined collaborative linkages strength is 145 and it varied from 26 to 111 linkages per organization. The strength of collaborative linkages between one-to-one organizations varied from 1 to 13 (Table 7). CNRS, France, University of Ulm, Germany and Gottfried Wilhelm Leibniz Universitat Hannover, Germany registered the highest number of collaborative linkages (111, 107 and 104). Similarly, University of Missouri, USA, Ferdinand-Braun Institut Leibniz-Institut fur Ho Hochstfrequenztechnik, Germany and Naval Research Lab., USA registered the lowest linkages (26, 31 and 36). In terms of one-to-many organizations links, -- Humboldt-Universitat zu Berlin, Germany and Ferdinand-Braun Institut Leibniz-Institut fur Ho Hochstfrequenztechnik, Germany and L’Observatoires de Paris, France and Systemes de Reference Temps-Espace, France -- registered the highest number of collaborative linkages (13 each), followed by Naval Research Lab., USA and University of Missouri, USA and LENS European Lab for Non-Linear Spectroscopy, Italy and Universersita degli Studi di Firenze, Italy (12 linkages each), Gottfried Wilhelm Leibniz Universitat Hannover, Germany and Humboldt-Universitat zu Berlin, Germany and Gottfried Wilhelm Leibniz Universitat Hannover, Germany and Humboldt-Universitat zu Berlin, Germany (11 linkages each), CNRS, France and L’Observatoires de Paris, France and CNRS, France and Systemes de Reference Temps-Espace, France (9 linkages each), etc. The collaborative networks between 15 top institutes were mapped through biblioshiny tool and represented in Fig. 3. The box represents each note and its size depends upon the number of its publications and the lines indicates the links between collaborating institutions. The various colors in the visualization networks represent the cooperation clusters. The largest cluster (in green) represents the University of Ulm, Germany, Gottfried Wilhelm Leibniz Universitat Hannover, Germany, Humboldt-Universitat zu Berlin, Germany and Ferdinand-Braun Institut Leibniz-Institut fur Ho Hochstf requenztechnik, Germany.

Table 7.

Quantum sensing research: collaborative linkages among most productive organiztions 1991-2020

Fig. 3.

Institutional collaboration networks chart on quantum sensing research

5.5 Top 15 most productive authors

In all, a total of 389 authors contributed to global research in the domain of quantum sensing during 1991-2020. Of these, 342 authors published 1-5 papers each,34 authors 6-10 papers each, 12 authors 11-20 papers each and 1 author 21 papers. Of the top 25 authors, 6 were from Germany, 4 each from Italy and USA and 1 from Israel. The research productivity of the top 15 most productive authors varied from 9 to 21 publications per author. Together they accounted for a 34.18% (201) global publications share and a 40.26% (2850) global citations share. The scientometric profile of top 15 most productive organizations is presented in (Table 8).

Table 8.

Scientometirc profile of top 15 most productive in quantum sensing research 1991-2020

On further analysis, it was observed that: (i) Six of top 15 authors contributed publications above the average productivity (13.4) of all 15 organizations: A. Peters (21 papers), M. Lanzagorta (20 papers), J.F. Smith (16 papers), F. Jelezko and A. Wicht (15 papers each) and P. Cappellars (14 papers); (ii) Five authors registered citation per paper and relative citation index above their group average (14.18 and 1.18): P. Cappellars (61.79 and 5.13), F. Jelezko (26.47 and 2.20), A. Retzker (19.73 and 1.64), G.M.Tino (19.40 and 1.61) and M.B. Plenio(16.75 and 1.39).

5.5.1 Collaborative linkages among top 15 authors

All of the top 15 most productive authors, except two, collaborated in quantum sensing research. Their combined collaborative linkages strength is 1461 links and it varied from 17-72 links per author. The number of collaborative linkages between one-to-one authors varied from 4 to 13 (Table 9). A. Peters, E. M. Rasel and W. Ertmer registered the highest number of collaborative linkages (303, 215 and 198. J. Uhlmann, M. Lanzagorta and A. Retzker registered the lowest collaborative linkages (29, 33 and 45) among top 15 authors. Among the author to author collaboration linkages, A. Peters and A. Wicht and M. Lanzagorta and J. Uhlmann registered the highest number of collaborative linkages (13 each), followed by A. Peters – E. M. Rasel, W. Ertmer – E. M. Rasel, M. Barbieri – I. Gianani and A. Peters – E. M. Rasel (11 linkages each), each. As seen from collaborative network of top 15 authors was mapped by using the biblioshiny tool (Fig. 4). The thickness of the box (node) is proportional to its number of collaborative publications. The bigger the box size and the text font size, the more the number of collaborative publications. The map suggested that there has been active collaboration amongst the most productive authors.

Table 9.

Quantum sensing research: collaborative linkages among top 15 most productive authors

Fig. 4.

Collaborative linkages network of top authors on Quantum Sensing research from 1991 to 2020.

5.6 Channels of research communication

Of the total world output in quantum sensing research, 59.52% (350) appeared in 141 journals, 36.73% (216) in conference proceedings, 1.87% (11) in book series, 1.02% (6) as books and 0.85% (5) in trade journals. Of the 141 journals, 130 published 1-5 papers each, 5 published 6-10 papers each, 4 published 11-20 papers each and 2 journals published 21-28 papers each during 1991-2020.

The top 15 most productive journals accounted for a 48.0% share of the global output in quantum sensing research during the period. The top 5 most productive journals were: Physical Review A (30 papers), Physical Review Letters (28 papers), New Journal of Physics (23 papers), Physical Review Applied (17 papers) and Nano Letters (11 papers). The top 5 most impactful journals were: Agriculture & Forest Meterology (69.67), Science (42.17), Physical Review A (34.0), Nature Communication (30.56) and Physical Review Letters (25.07). A list of top 15 most productive journals is shown in Table 10.

Table 10.

List of top 15 most productive journals in quantum sensing

Agriculture & Forest Meteorology, Physical Review Letters and Science and 1 paper each in Angewandte Chimie-International Edition, Annual Review of Physical Chemistry, Contemporary Physics, Nature Photonics., New Journal of Physics, Physical Review A and Review of Modern Physics

6. Summary and Conclusion

The study analyses the global output in quantum sensing research on metrics with the aim to understand its status and performance at national, institutional, and author level. The study identified key players in quantum sensing research such as key countries, key institutions, key authors, and key areas of research. The study also presented a visual view of network collaborative relationships between key players. The global research on this theme comprised a total of 588 publications in the 30-year period 1991-2020. The global research registered a 14.85% annual average growth, its 15-year cumulative output increased by 16.37%, and its research received an average of 12.04 citations per paper (CPP) since publication during the period. A 43.03% share of global output appeared as sponsored research papers. Although participation in quantum sensing research is global (with a participation of 48 countries), but only the top two countries (the USA and Germany) account for a 50% share. The other productive countries in the list of top-10 are the U.K., China, Italy, Japan, France and Australia but their global share is comparatively small ranging from 5.27% to 9.86% share of world output. Although a total of 389 authors from 293 organizations had participated in global quantum sensing research, but a significant share (35.52% and 34.18%) of global output is dominated by the top 15 most productive organizations and top 15 most productive authors respectively. Among the top 15 participating organizations, 4 each come from the USA, Germany and Italy and 3 from France). Among top 15 most productive authors, 6 come from Germany, 4 each from Italy and USA and 1 from Israel. The journals such as Physical Review A (30 papers), Physical Review Letters (28 papers), New Journal of Physics (23 papers) and Physical Review Applied (17 papers) lead in global publication productivity. In addition, in terms of most cited journals, Agriculture & Forest Meteorology (69.67), Science (42.17), Physical Review A (34.0) and Nature Communication (30.56) top the most cited journals list. The global research in the field of quantum sensors is distributed across seven disciplines. Of these, Physics & Astronomy, Engineering and Materials Science accounted for a major share (76.02%, 45.07% and 42.52% respectively) to the global output.

The research in the field of quantum sensing is still at a nascent stage of its development. Even after 30-year research into quantum sensing area the body of literature in the subject is still very small, standing just at a total of 588 publications, nearly 19.6 publications globally per year. The USA, Germany, and Italy are the top three countries that have come to dominate the domain of quantum sensing research at a global level. This conclusion is based on country-wise research productivity, organization-wise productivity, and publication of research output that appeared mainly in research journals that have country of their publication in western countries. Further, this study finds that Massachusetts Institute of Technology, USA and University of Ulm, Germany have emerged both as most productive organizations and the most cited organizations. In addition, ETH, Zurich, though it is not ranking the list of top 15 most productive organizations, but it emerged as one of top three highly cited organizations. This confirms the view that there is very little correlation between most cited organizations and most productive organizations. The contribution of Asian countries in the growth and development of research in the subject is marginal. The findings in this study should be of interest to researchers, policy formulators and other actors, especially those from the developing countries. The findings in this study should be of interest to stakeholders in the country in planning R&D investments for strengthening research infrastructure, initiating new programmes aimed at international collaboration, and in undertaking fresh programmes for manpower development in the domain of quantum sensing research.

References

• CNRS. (2021). Sensors, the other quantum revolution. Retrieved from https://news.cnrs.fr/articles/sensors-the-other-quantum-revolution
• Degen, C. L., Reinhard, F., & Cappellaro, P. (2017). Quantum sensing. Reviews of Modern Physics, 89(3), 035002. [https://doi.org/10.1103/RevModPhys.89.035002]
• Dhawan, S. M., Gupta, B. M., & Bhusan, S. (2018). Global publications output in quantum computing research: A scientometric assessment during 2007-16. Emerging Science Journal, 2(4), 228-237. [https://doi.org/10.28991/esj-2018-01147]
• Dhawan, S. M., Gupta, B. M., & Mamdapur, G. M. (2021). Quantum machine learning: A scientometric assessment of global Publications during 1999-2020. International Journal of Knowledge Content Development & Technology, 11(3), 29–44. [https://doi.org/10.5865/IJKCT.2021.11.3.029]
• Fuentes, I., & Bouyer, P. (2021). Quantum Sensing and Metrology. NewYork: AIP Publishing LLC.
• Gupta, B. M., & Dhawan, S. M. (2020a). Quantum neural network (QNN) research a scientometrics assessment of global publications during 1990-2019. International Journal of Information Dissemination and Technology, 10(3), 168–174. [https://doi.org/10.5958/2249-5576.2020.00030.8]
• Gupta, B. M., & Dhawan, S. M. (2020b). Quantum robotics: A scientometrics assessment of global publications during 1993-2020. International Journal of Information Dissemination and Techno logy, 10(4), 195–200. [https://doi.org/10.5958/2249-5576.2020.00036.9]
• Gupta, B. M., Dhawan, S. M., & Mamdapur, G. M. (2021). Quantum cryptography research: A scientometric assessment of global publications during 1992-2019. Science & Technology Libraries, 40(3), 282-300. [https://doi.org/10.1080/0194262X.2021.1892563]
• Gupta, B. M., Dhawan, S. M., Ashok, K., & Walke, R. (2021). Quantum dots research in India: A bibliometric study of the publications output for the period 2000-2019. International Journal of Information Dissemination and Technology, 11(1), 44–49. [https://doi.org/10.5958/2249-5576.2021.00006.6]
• Ibrahim, A.-B. M. A., Julius, R., & Choudhury, P. K. (2021). Progress in quantum electronics research: A bibliometric analysis. Journal of Electromagnetic Waves and Applications, 35(4), 549–565. [https://doi.org/10.1080/09205071.2020.1821298]
• NATO. (2020). Quantum position navigation and timing for NATO platforms. North Atlantic Treaty Organization Science and Technology Organization. Retrieved from https://www.sto.nato.int/Lists/test1/activitydetails.aspx?ID=16610
• Pirandola, S., Bardhan, B. R., Gehring, T., Weedbrook, C., & Lloyd, S. (2018). Advances in photonic quantum sensing. Nature Photonics, 12(12), 724–733. Retrieved from https://www.nature.com/articles/s41566-018-0301-6 [https://doi.org/10.1038/s41566-018-0301-6]
• Seskir, Z. C., & Aydinoglu, A. U. (2021). The landscape of academic literature in quantum technologies. International Journal of Quantum Information, 19(02), 2150012. [https://doi.org/10.1142/S021974992150012X]
• Terekhov, A. I. (2020). Bibliometric trends in quantum information processing. Scientific and Technical Information Processing, 47(2), 94–103. [https://doi.org/10.3103/S0147688220020021]
• Tetienne, J. P., & Hall, L. T. (2021). Special Issue Sensors Based on Quantum Phenomena. Sensors Based on Quantum Phenomena. Retrieved from https://www.mdpi.com/journal/sensors/special_issues/Quantum_Phenomena
• Tolcheev, V. O. (2018). Scientometric analysis of the current state and prospects of the development of quantum technologies. Automatic Documentation and Mathematical Linguistics, 52(3), 121–133. [https://doi.org/10.3103/S000510551803007X]