{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T21:59:20Z","timestamp":1768255160427,"version":"3.49.0"},"reference-count":22,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T00:00:00Z","timestamp":1678752000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12034013"],"award-info":[{"award-number":["12034013"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We demonstrated a method for in situ temporal characterization of an intense femtosecond laser pulse around its focus where the laser intensity exceeds 1014 W\/cm2. Our method is based on the second harmonic generation (SHG) by a relatively weak femtosecond probe pulse and the intense femtosecond pulses under analysis in the gas plasma. With the increase in the gas pressure, it was found that the incident pulse evolves from a Gaussian profile to a more complicated structure featured by multiple peaks in the temporal domain. Numerical simulations of filamentation propagation support the experimental observations of temporal evolution. This simple method can be applied to many situations involving femtosecond laser\u2013gas interaction, when the temporal profile of the femtosecond pump laser pulse with an intensity above 1014 W\/cm2 cannot be measured in traditional ways.<\/jats:p>","DOI":"10.3390\/s23063101","type":"journal-article","created":{"date-parts":[[2023,3,14]],"date-time":"2023-03-14T06:14:58Z","timestamp":1678774498000},"page":"3101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Revealing Local Temporal Profile of Laser Pulses of Intensity above 1014 W\/cm2"],"prefix":"10.3390","volume":"23","author":[{"given":"Qi","family":"Lu","sequence":"first","affiliation":[{"name":"Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, 516, Jungong Road, Shanghai 200093, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, 516, Jungong Road, Shanghai 200093, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arnaud","family":"Couairon","sequence":"additional","affiliation":[{"name":"Centre de Physique Th\u00e9orique, CNRS, Ecole Polytechnique, F-91128 Palaiseau, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0821-7322","authenticated-orcid":false,"given":"Yi","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, 516, Jungong Road, Shanghai 200093, China"},{"name":"CAS Center for Excellence in Ultra-Intense Laser Science, Shanghai 201800, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1364\/AOP.1.000308","article-title":"Characterization of ultrashort electromagnetic pulses","volume":"1","author":"Walmsley","year":"2009","journal-title":"Adv. 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