{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T23:25:15Z","timestamp":1775863515025,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2013,10,22]],"date-time":"2013-10-22T00:00:00Z","timestamp":1382400000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A simple and compact fiber optic sensor based on a two-core fiber is demonstrated for high-performance measurements of refractive indices (RI) of liquids. In order to demonstrate the suitability of the proposed sensor to perform high-sensitivity sensing in a variety of applications, the sensor has been used to measure the RI of binary liquid mixtures. Such measurements can accurately determine the salinity of salt water solutions, and detect the water content of adulterated alcoholic beverages. The largest sensitivity of the RI sensor that has been experimentally demonstrated is 3,119 nm per Refractive Index Units (RIU) for the RI range from 1.3160 to 1.3943. On the other hand, our results suggest that the sensitivity can be enhanced up to 3485.67 nm\/RIU approximately for the same RI range.<\/jats:p>","DOI":"10.3390\/s131014200","type":"journal-article","created":{"date-parts":[[2013,10,23]],"date-time":"2013-10-23T07:45:42Z","timestamp":1382514342000},"page":"14200-14213","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["A Highly Sensitive Fiber Optic Sensor Based on Two-Core Fiber for Refractive Index Measurement"],"prefix":"10.3390","volume":"13","author":[{"given":"Jos\u00e9","family":"Guzm\u00e1n-Sep\u00falveda","sequence":"first","affiliation":[{"name":"Fiber and Integrated Optics Laboratory, Electronics Engineering Department, UAM Reynosa-Rodhe, Universidad Aut\u00f3noma de Tamaulipas, Carr. Reynosa-San Fernando S\/N, Reynosa, Tamaulipas 88779, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rafael","family":"Guzm\u00e1n-Cabrera","sequence":"additional","affiliation":[{"name":"NanoBioPhotonics Group, DICIS, University of Guanajuato, Salamanca, Guanajuato 368850, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miguel","family":"Torres-Cisneros","sequence":"additional","affiliation":[{"name":"NanoBioPhotonics Group, DICIS, University of Guanajuato, Salamanca, Guanajuato 368850, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jos\u00e9","family":"S\u00e1nchez-Mondrag\u00f3n","sequence":"additional","affiliation":[{"name":"Photonics and Optical Physics Laboratory, Optics Department, INAOE, Puebla, Puebla 72000, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"May-Arrioja","sequence":"additional","affiliation":[{"name":"Fiber and Integrated Optics Laboratory, Electronics Engineering Department, UAM Reynosa-Rodhe, Universidad Aut\u00f3noma de Tamaulipas, Carr. Reynosa-San Fernando S\/N, Reynosa, Tamaulipas 88779, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,10,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1364\/OL.34.000617","article-title":"Refractometry based on a photonic crystal fiber interferometer","volume":"34","author":"Jha","year":"2009","journal-title":"Opt. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3221","DOI":"10.1364\/OL.36.003221","article-title":"Refractometer based on an asymmetrical twin-core fiber Michelson interferometer","volume":"36","author":"Zhou","year":"2011","journal-title":"Opt. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1447","DOI":"10.1364\/OE.17.001447","article-title":"Photonic crystal fiber interferometer for chemical vapor detection with high sensitivity","volume":"17","author":"Villatoro","year":"2009","journal-title":"Opt. 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