{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,16]],"date-time":"2026-03-16T12:36:48Z","timestamp":1773664608519,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,15]],"date-time":"2021-12-15T00:00:00Z","timestamp":1639526400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Innovation Foundation, Cyprus","award":["EXCELLENCE\/0918\/0324 \"T-Sense\""],"award-info":[{"award-number":["EXCELLENCE\/0918\/0324 \"T-Sense\""]}]},{"name":"Research Innovation Foundation, Cyprus","award":["POSTDOC\/0718(sp.ext)\/0003"],"award-info":[{"award-number":["POSTDOC\/0718(sp.ext)\/0003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work presents an extensive, comparative study of the gamma and electron radiation effects on the behaviour of femtosecond laser-inscribed fibre Bragg gratings (FBGs) using the point-by-point and plane-by-plane inscription methods. The FBGs were inscribed in standard telecommunication single mode silica fibre (SMF28) and exposed to a total accumulated radiation dose of 15 kGy for both gamma and electron radiation. The gratings\u2019 spectra were measured and analysed before and after the exposure to radiation, with complementary material characterisation using Fourier transform infrared (FTIR) spectroscopy. Changes in the response of the FBGs\u2019 temperature coefficients were analysed on exposure to the different types of radiation, and we consider which of the two inscription methods result in gratings that are more robust in such harsh environments. Moreover, we used the FTIR spectroscopy to locate which chemical bonds are responsible for the changes on temperature coefficients and which are related with the optical characteristics of the FBGs.<\/jats:p>","DOI":"10.3390\/s21248379","type":"journal-article","created":{"date-parts":[[2021,12,15]],"date-time":"2021-12-15T21:47:36Z","timestamp":1639604856000},"page":"8379","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Comparative Study of \u03b3- and e-Radiation-Induced Effects on FBGs Using Different Femtosecond Laser Inscription Methods"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5912-9138","authenticated-orcid":false,"given":"Antreas","family":"Theodosiou","sequence":"first","affiliation":[{"name":"Photonics and Optical Sensors Research Laboratory (PhOSLab), Cyprus University of Technology, Saripolou 33, Limassol 3036, Cyprus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9075-0619","authenticated-orcid":false,"given":"Arnaldo","family":"Leal-Junior","sequence":"additional","affiliation":[{"name":"Graduate Program in Electrical Engineering, Federal University of Espirito Santo, Fernando Ferrari Avenue, Vitoria 29075-910, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8596-5092","authenticated-orcid":false,"given":"Carlos","family":"Marques","sequence":"additional","affiliation":[{"name":"i3N, Department of Physics, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0687-3967","authenticated-orcid":false,"given":"Anselmo","family":"Frizera","sequence":"additional","affiliation":[{"name":"Graduate Program in Electrical Engineering, Federal University of Espirito Santo, Fernando Ferrari Avenue, Vitoria 29075-910, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4376-5594","authenticated-orcid":false,"given":"Antonio J. S.","family":"Fernandes","sequence":"additional","affiliation":[{"name":"i3N, Department of Physics, University of Aveiro, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2041-4924","authenticated-orcid":false,"given":"Andrei","family":"Stancalie","sequence":"additional","affiliation":[{"name":"Center for Advanced Laser Technologies, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., RO-077125 Magurele, Romania"}]},{"given":"Andreas","family":"Ioannou","sequence":"additional","affiliation":[{"name":"Photonics and Optical Sensors Research Laboratory (PhOSLab), Cyprus University of Technology, Saripolou 33, Limassol 3036, Cyprus"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7893-3626","authenticated-orcid":false,"given":"Daniel","family":"Ighigeanu","sequence":"additional","affiliation":[{"name":"Center for Advanced Laser Technologies, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., RO-077125 Magurele, Romania"}]},{"given":"Razvan","family":"Mihalcea","sequence":"additional","affiliation":[{"name":"Center for Advanced Laser Technologies, National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor St., RO-077125 Magurele, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7910-8801","authenticated-orcid":false,"given":"Constantin Daniel","family":"Negut","sequence":"additional","affiliation":[{"name":"\u201cHoria Hulubei\u201d National Institute for R&D in Physics and Nuclear Engineering, 30 Reactorului St., RO-077125 Magurele, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4541-092X","authenticated-orcid":false,"given":"Kyriacos","family":"Kalli","sequence":"additional","affiliation":[{"name":"Photonics and Optical Sensors Research Laboratory (PhOSLab), Cyprus University of Technology, Saripolou 33, Limassol 3036, Cyprus"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4309","DOI":"10.1063\/1.1148392","article-title":"Fiber Bragg gratings","volume":"68","author":"Othonos","year":"1997","journal-title":"Rev. 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