{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T15:27:51Z","timestamp":1760369271917,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2016,4,7]],"date-time":"2016-04-07T00:00:00Z","timestamp":1459987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>In the scope of miniaturized optical sensors for liquid refractometry, this work details the design, numerical simulation, and experimental characterization of a Fabry-P\u00e9rot resonator consisting of two deeply-etched silicon cylindrical mirrors with a micro-tube in between holding the liquid analyte under study. The curved surfaces of the tube and the cylindrical mirrors provide three-dimensional light confinement and enable achieving stability for the cavity illuminated by a Gaussian beam input. The resonant optofluidic cavity attains a high-quality factor (Q)\u2014over 2800\u2014which is necessary for a sensitive refractometer, not only by providing a sharp interference spectrum peak that enables accurate tracing of the peak wavelengths shifts, but also by providing steep side peaks, which enables detection of refractive index changes by power level variations when operating at a fixed wavelength. The latter method can achieve refractometry without the need for spectroscopy tools, provided certain criteria explained in the details are met. By experimentally measuring mixtures of acetone-toluene with different ratios, refractive index variations of 0.0005 &lt; \u0394n &lt; 0.0022 could be detected, with sensitivity as high as 5500 \u03bcW\/RIU.<\/jats:p>","DOI":"10.3390\/mi7040062","type":"journal-article","created":{"date-parts":[[2016,4,7]],"date-time":"2016-04-07T11:52:48Z","timestamp":1460029968000},"page":"62","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Optofluidic Fabry-P\u00e9rot Micro-Cavities Comprising Curved Surfaces for Homogeneous Liquid Refractometry\u2014Design, Simulation, and Experimental Performance Assessment"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9472-1084","authenticated-orcid":false,"given":"Noha","family":"Gaber","sequence":"first","affiliation":[{"name":"Laboratoire Electronique, Syst\u00e8mes de Communication et Microsyst\u00e8mes, Universit\u00e9 Paris-Est, ESIEE Paris, ESYCOM EA 2552, 93162 Noisy-le-Grand, France"},{"name":"Center for Nanotechnology, Zewail City of Science and Technology, Sheikh Zayed District, 6th of October City, 12588 Giza, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5385-4697","authenticated-orcid":false,"given":"Yasser","family":"Sabry","sequence":"additional","affiliation":[{"name":"Electronics and Electrical Communication Engineering, Faculty of Engineering, Ain-Shams University, 1 Elsarayat St., Abbassia, Cairo 11517, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fr\u00e9d\u00e9ric","family":"Marty","sequence":"additional","affiliation":[{"name":"Laboratoire Electronique, Syst\u00e8mes de Communication et Microsyst\u00e8mes, Universit\u00e9 Paris-Est, ESIEE Paris, ESYCOM EA 2552, 93162 Noisy-le-Grand, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2342-7149","authenticated-orcid":false,"given":"Tarik","family":"Bourouina","sequence":"additional","affiliation":[{"name":"Laboratoire Electronique, Syst\u00e8mes de Communication et Microsyst\u00e8mes, Universit\u00e9 Paris-Est, ESIEE Paris, ESYCOM EA 2552, 93162 Noisy-le-Grand, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"634","DOI":"10.1039\/C5LC01445J","article-title":"Cell refractive index for cell biology and disease diagnosis: Past, present and future","volume":"16","author":"Liu","year":"2016","journal-title":"Lab Chip"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4091","DOI":"10.1364\/AO.50.004091","article-title":"Refractive index measured by laser beam displacement at \u03bb = 1064 nm for solvents and deuterated solvents","volume":"50","author":"Shelton","year":"2011","journal-title":"Appl. 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