{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T05:28:32Z","timestamp":1776749312695,"version":"3.51.2"},"reference-count":26,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T00:00:00Z","timestamp":1763942400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["21-72-30024-\u03a0"],"award-info":[{"award-number":["21-72-30024-\u03a0"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Raman lasers based on multimode graded-index (GRIN) fibers directly pumped by laser diodes are the object of intensive research, promising to produce high-power, high-quality beams at new wavelengths. In this paper, we demonstrate a pulsed operation of such a laser based on a 1 km 100\/140 GRIN fiber in which a resonator is formed by a pair of FBGs: a high-reflective broadband input FBG and a tunable narrowband output FBG inscribed by fs laser pulses in the fundamental mode area of the core. In addition to beam quality improvement, the output FBG modulated by a piezoelectric nanopositioner with a frequency of 20\u2013180 Hz generates laser pulses with a duration of 23\u20131.2 ms, respectively. The maximum power reached is 22 watts, and the signal spectrum widens significantly with increased pumping (&gt;2 nm from the central wavelength of 976 nm). The pulse generation method used in this work introduces wavelength chirp in the individual pulse, which can be used in sensing and other applications.<\/jats:p>","DOI":"10.3390\/mi16121315","type":"journal-article","created":{"date-parts":[[2025,11,24]],"date-time":"2025-11-24T14:59:04Z","timestamp":1763996344000},"page":"1315","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Pulsed Raman Lasing in Diode-Pumped Multimode Graded-Index Fiber with Tuned Femtosecond-Laser-Inscribed Bragg Grating"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-1271-2557","authenticated-orcid":false,"given":"Alexey G.","family":"Kuznetsov","sequence":"first","affiliation":[{"name":"Institute of Automation and Electrometry, 1 Ac. Koptyug Ave., Novosibirsk 630090, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0368-0761","authenticated-orcid":false,"given":"Vadim S.","family":"Terentyev","sequence":"additional","affiliation":[{"name":"Institute of Automation and Electrometry, 1 Ac. Koptyug Ave., Novosibirsk 630090, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexander V.","family":"Dostovalov","sequence":"additional","affiliation":[{"name":"Institute of Automation and Electrometry, 1 Ac. Koptyug Ave., Novosibirsk 630090, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilya N.","family":"Nemov","sequence":"additional","affiliation":[{"name":"Institute of Automation and Electrometry, 1 Ac. Koptyug Ave., Novosibirsk 630090, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3559-6839","authenticated-orcid":false,"given":"Sergey A.","family":"Babin","sequence":"additional","affiliation":[{"name":"Institute of Automation and Electrometry, 1 Ac. Koptyug Ave., Novosibirsk 630090, Russia"},{"name":"Physics Department, Novosibirsk State University, 2 Pirogov Str., Novosibirsk 630090, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"876","DOI":"10.1364\/OPTICA.5.000876","article-title":"Hybrid integration of silicon photonics circuits and InP lasers by photonic wire bonding","volume":"5","author":"Billah","year":"2018","journal-title":"Optica"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tian, W., Wang, Y., Dang, H., Hou, H., and Xi, Y. (2025). 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