Full space-time ultrafast self-focusing of spherical Airy wavepackets

Nature Physics (2026)Cite this article The ability to precisely focus optical beams is crucial for numerous applications, including imaging. The slow intensity transitions of conventional Gaussian beams near the focal point limit their effectiveness in scenarios requiring sharp focusing. Ultrafast self-focusing of circular Airy beams has been reported in two dimensions. Here we demonstrate this capability for spherical Airy wavepackets, a three-dimensional light field with an Airy function distribution in the radial direction. We sculpt spherical Airy wavepackets to exhibit ultrafast self-focusing with a substantially reduced depth of focus, compared with both conventional Gaussian beams and circular Airy beams. Our measurements confirm the wavepacket’s nonlinear intensity increase and tight spatiotemporal confinement. The superior focusing dynamics of spherical Airy wavepackets are broadly applicable to high-resolution imaging, nonlinear optics and optical trapping. Overcoming current limitations from pixelated modulation devices, such as spatial light modulators, could further enhance focusing performance, paving the way for advanced applications in biomedical imaging, laser processing and ultrafast optics.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutThe data related to this study are available under restricted access due to data privacy laws. The size of the dataset exceeds the limit of public data repositories. Access can be obtained by reasonable request to the corresponding author.The code related to this study is available upon reasonable request to the corresponding author.Olarte, O. E., Andilla, J., Gualda, E. J. & Loza-Alvarez, P. Light-sheet microscopy: a tutorial. Adv. Opt. Photonics 10, 111–179 (2018).Article ADS Google Scholar Nwaneshiudu, A. et al. Introduction to confocal microscopy. J. Invest. Dermatol. 132, 1–5 (2012).Article Google Scholar Harilal, S. S., Freeman, J. R., Diwakar, P. K. & Hassanein, A. Femtosecond laser ablation: fundamentals and applications. Springer Ser. Opt. Sci. 182, 143–166 (2014).

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Beams 14, 112802 (2011).Article ADS Google Scholar Chen, J. et al. Automated close loop system for three-dimensional characterization of spatiotemporal optical vortex. Front. Phys. 9, 31 (2021).Article Google Scholar Download referencesWe acknowledge financial support from National Key Research and Development Program of China (grant no. 2025YFF0515100 (Q.Z)), National Natural Science Foundation of China (NSFC) (grant nos. 12434012, 62535013 (Q.Z.) and 12474336 (Q.C.)), the Shanghai Science and Technology Committee (grant nos. 24JD1402600 (Q.Z.) and 24QA2705800 (Q.C.)), National Research Foundation of Korea (NRF) funded by the Korea government (MSIT) (grant no. 2022R1A2C1091890 (A.C.)) and Global – Learning & Academic research institution for Master’s·PhD students, and Postdocs (LAMP) Program of the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education (grant no. RS-2023-00301938 (A.C.)). Q.Z. also acknowledges support by the Key Project of Westlake Institute for Optoelectronics (grant no. 284 2023GD007 (Q.Z.)).These authors contributed equally: Qian Cao, Nianjia Zhang.School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai, ChinaQian Cao, Nianjia Zhang & Qiwen ZhanZhangjiang Laboratory, Shanghai, ChinaQian Cao & Qiwen ZhanDepartment of Physics, Pusan National University, Busan, Republic of KoreaAndy ChongInstitute for Future Earth, Pusan National University, Busan, Republic of KoreaAndy ChongZhejiang Key Laboratory of 3D Micro/Nano Fabrication and Characterization, Department of Electronic and Information Engineering, School of Engineering, Westlake University, Hangzhou, ChinaQiwen ZhanWestlake Institute for Optoelectronics, Hangzhou, ChinaQiwen ZhanSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarQ.C., A.C. and Q.Z. proposed the original idea and initiated this project. Q.C. and N.Z. designed and performed the experiments. Q.C., N.Z. and Q.Z. analysed the data. Q.C., N.Z., A.C. and Q.Z. prepared the manuscript. Q.C. and Q.Z. supervised the project. All authors contributed to the discussion and writing of the manuscript.Correspondence to Qian Cao, Andy Chong or Qiwen Zhan.The authors declare no competing interests.Nature Physics thanks Nikolaos Efremidis and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Supplementary Figs. 1 and 2 and Refs. 1–4.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsCao, Q., Zhang, N., Chong, A. et al. Full space-time ultrafast self-focusing of spherical Airy wavepackets. Nat. Phys. (2026). https://doi.org/10.1038/s41567-026-03237-zDownload citationReceived: 04 July 2025Accepted: 04 March 2026Published: 01 April 2026Version of record: 01 April 2026DOI: https://doi.org/10.1038/s41567-026-03237-zAnyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative