{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T10:03:13Z","timestamp":1771063393954,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,20]],"date-time":"2018-04-20T00:00:00Z","timestamp":1524182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>It is presented the fabrication and characterization of optical fiber sensors for refractive index measurement based on localized surface plasmon resonance (LSPR) with gold nano-islands obtained by single and by repeated thermal dewetting of gold thin films. Thin films of gold deposited on silica (SiO2) substrates and produced by different experimental conditions were analyzed by Scanning Electron Microscope\/Dispersive X-ray Spectroscopy (SEM\/EDS) and optical means, allowing identifying and characterizing the formation of nano-islands. The wavelength shift sensitivity to the surrounding refractive index of sensors produced by single and by repeated dewetting is compared. While for the single step dewetting, a wavelength shift sensitivity of ~60 nm\/RIU was calculated, for the repeated dewetting, a value of ~186 nm\/RIU was obtained, an increase of more than three times. It is expected that through changing the fabrication parameters and using other fiber sensor geometries, higher sensitivities may be achieved, allowing, in addition, for the possibility of tuning the plasmonic frequency.<\/jats:p>","DOI":"10.3390\/s18041267","type":"journal-article","created":{"date-parts":[[2018,4,23]],"date-time":"2018-04-23T04:29:17Z","timestamp":1524457757000},"page":"1267","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Plasmonic Optical Fiber Sensor Based on Double Step Growth of Gold Nano-Islands"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3810-5943","authenticated-orcid":false,"given":"Jos\u00e9 M. M. M.","family":"De Almeida","sequence":"first","affiliation":[{"name":"CAP\/INESC TEC\u2014Technology and Science and FCUP\u2014Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"},{"name":"Department of Physics, School of Sciences and Technology, University of Tr\u00e1s-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal"}]},{"given":"Helena","family":"Vasconcelos","sequence":"additional","affiliation":[{"name":"CAP\/INESC TEC\u2014Technology and Science and FCUP\u2014Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1484-2068","authenticated-orcid":false,"given":"Pedro A. S.","family":"Jorge","sequence":"additional","affiliation":[{"name":"CAP\/INESC TEC\u2014Technology and Science and FCUP\u2014Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6205-9479","authenticated-orcid":false,"given":"Luis","family":"Coelho","sequence":"additional","affiliation":[{"name":"CAP\/INESC TEC\u2014Technology and Science and FCUP\u2014Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25208","DOI":"10.3390\/s151025208","article-title":"Fiber-optic chemical sensors and fiber-optic bio-sensors","volume":"15","year":"2015","journal-title":"Sensors"},{"key":"ref_2","first-page":"400","article-title":"Fiber optic refractometers: A brief qualitative review","volume":"3","author":"Nath","year":"2016","journal-title":"Adv. Res. Electr. Electron. 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