{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T15:49:01Z","timestamp":1761061741018,"version":"build-2065373602"},"reference-count":12,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,11,30]],"date-time":"2022-11-30T00:00:00Z","timestamp":1669766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Universidades of Spain","award":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"],"award-info":[{"award-number":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033 and FEDER \u201cA way to make Europe\u201d","award":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"],"award-info":[{"award-number":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033 and European Union \u201cNext generation EU\u201d\/PTR","award":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"],"award-info":[{"award-number":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"]}]},{"name":"National Funds through the Portuguese funding agency, FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"],"award-info":[{"award-number":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"]}]},{"name":"FCT, Portugal","award":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"],"award-info":[{"award-number":["CAS21\/00351","PID2019-107270RB-C22","PDC2021-121172-C21","TED2021-130378B-C22","UIDB\/50014\/2020","2020.05297.BD"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, an interrogation system based on an erbium-doped fiber ring cavity for refractive index measurements is presented and experimentally demonstrated. This cavity ring includes a 1 \u00d7 3 coupler wherein one of the fiber output ports is used to increase the optical power of the system by means of an FBG used as a reflector. The other two output ports are used as a refractive index sensing head and reference port, respectively. An experimental demonstration of this proposed sensor system for the measurement of a distinct refractive index is presented.<\/jats:p>","DOI":"10.3390\/s22239315","type":"journal-article","created":{"date-parts":[[2022,11,30]],"date-time":"2022-11-30T08:46:41Z","timestamp":1669798001000},"page":"9315","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Ring Cavity Erbium-Doped Fiber for Refractive Index Measurements"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6856-9143","authenticated-orcid":false,"given":"Rosa Ana","family":"Perez-Herrera","sequence":"first","affiliation":[{"name":"Department of Electrical, Electronic and Communication Engineering, Public University of Navarra, 31006 Pamplona, Spain"},{"name":"Institute of Smart Cities (ISC), Public University of Navarra, 31006 Pamplona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1828-4633","authenticated-orcid":false,"given":"Liliana","family":"Soares","sequence":"additional","affiliation":[{"name":"INESC TEC, R. 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Actuators B-Chem."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Shaimerdenova, M., Ayupova, T., Sypabekova, M., and Tosi, D. (2020). Fiber Optic Refractive Index Sensors Based on a Ball Resonator and Optical Backscatter Interrogation. Sensors, 20.","DOI":"10.3390\/s20216199"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5665","DOI":"10.1016\/j.optcom.2011.08.049","article-title":"Fiber optic intensity sensor referenced with a virtual delay line","volume":"284","author":"Fernandes","year":"2011","journal-title":"Opt. Commun."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"034017","DOI":"10.1088\/0957-0233\/20\/3\/034017","article-title":"Amplified CWDM self-referencing sensor network based on Phase-Shifted FBGs in transmissive configuration","volume":"20","author":"Elosua","year":"2009","journal-title":"Meas. Sci. Technol."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Zhao, X., Xie, Y., Hu, L., and Wu, B. (2021, January 19\u201321). A novel optical refractive index sensor based on VCSELs and gold nanoparticle arrays. Proceedings of the 4th International Conference on Electron Device and Mechanical Engineering (ICEDME), Guangzhou, China.","DOI":"10.1109\/ICEDME52809.2021.00032"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1016\/j.optlastec.2018.10.047","article-title":"Simultaneous measurement of refractive index and temperature using a Mach-Zehnder interferometer with forward core-cladding-core recoupling","volume":"111","author":"Jiao","year":"2019","journal-title":"Opt. Laser Technol."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/23\/9315\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:29:59Z","timestamp":1760146199000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/23\/9315"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,30]]},"references-count":12,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2022,12]]}},"alternative-id":["s22239315"],"URL":"https:\/\/doi.org\/10.3390\/s22239315","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,11,30]]}}}