Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies
if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the
same subfield and year (this is the minimum needed to enter the top 1%, not the average
within it), or reaches the top citation threshold in at least one of its specific research
topics.
Direct Link between Microwave and Optical Frequencies with a 300 THz Femtosecond Laser Comb
2000748 citationsRonald Holzwarth, Thomas Udem et al.profile →
Laser Frequency Combs for Astronomical Observations
2008461 citationsTilo Steinmetz, Tobias Wilken et al.Scienceprofile →
Cavity-enhanced dual-comb spectroscopy
2009397 citationsBirgitta Bernhardt, Akira Ozawa et al.Nature Photonicsprofile →
Optical frequency combs: Coherently uniting the electromagnetic spectrum
2020391 citationsThomas Udem et al.Scienceprofile →
The Rydberg constant and proton size from atomic hydrogen
2017241 citationsAxel Beyer, Lothar Maisenbacher et al.Scienceprofile →
Peers — A (Enhanced Table)
Peers by citation overlap · career bar shows stage (early→late)
cites ·
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This map shows the geographic impact of Thomas Udem's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Thomas Udem with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Thomas Udem more than expected).
This network shows the impact of papers produced by Thomas Udem. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Thomas Udem. The network helps show where Thomas Udem may publish in the future.
Co-authorship network of co-authors of Thomas Udem
This figure shows the co-authorship network connecting the top 25 collaborators of Thomas Udem.
A scholar is included among the top collaborators of Thomas Udem based on the total number of
citations received by their joint publications. Widths of edges
represent the number of papers authors have co-authored together.
Node borders
signify the number of papers an author published with Thomas Udem. Thomas Udem is excluded from
the visualization to improve readability, since they are connected to all nodes in the network.
Beyer, Axel, Lothar Maisenbacher, Arthur Matveev, et al.. (2017). The Rydberg constant and proton size from atomic hydrogen. Science. 358(6359). 79–85.241 indexed citations breakdown →
10.
Pohl, Randolf, F. Nez, Thomas Udem, et al.. (2016). Deuteron charge radius from spectroscopy data in atomic deuterium. arXiv (Cornell University).2 indexed citations
Bernhardt, Birgitta, Akira Ozawa, Patrick Jacquet, et al.. (2009). Cavity-enhanced dual-comb spectroscopy. Nature Photonics. 4(1). 55–57.397 indexed citations breakdown →
16.
Araujo-Hauck, Constanza, L. Pasquini, A. Manescau, et al.. (2007). Future wavelength calibration standards at ESO : the Laser Frequency Comb. Swinburne Research Bank (Swinburne University of Technology). 129. 24–26.6 indexed citations
17.
Udem, Thomas & F. Riehle. (2007). Frequency combs applications and optical frequency standards (reprinted from Proceedings of the International School of Physics "Enrico Fermi" Course CLXVI "Metrology and Fundamental Constants" pg 317-365, 2007). Rivista Del Nuovo Cimento. 30(12). 563–606.1 indexed citations
Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive
bibliographic database. While OpenAlex provides broad and valuable coverage of the global
research landscape, it—like all bibliographic datasets—has inherent limitations. These include
incomplete records, variations in author disambiguation, differences in journal indexing, and
delays in data updates. As a result, some metrics and network relationships displayed in
Rankless may not fully capture the entirety of a scholar's output or impact.