{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,21]],"date-time":"2026-03-21T01:08:20Z","timestamp":1774055300576,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2016,8,15]],"date-time":"2016-08-15T00:00:00Z","timestamp":1471219200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61275090"],"award-info":[{"award-number":["61275090"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61422507"],"award-info":[{"award-number":["61422507"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61227012"],"award-info":[{"award-number":["61227012"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National key research and development program of China","doi-asserted-by":"publisher","award":["2016YFF0100603"],"award-info":[{"award-number":["2016YFF0100603"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Innovation Program of Shanghai Municipal Education Commission","award":["14ZZ093"],"award-info":[{"award-number":["14ZZ093"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Atomic layer deposition (ALD) technology is introduced to fabricate a high sensitivity refractometer based on an adiabatic tapered optical fiber. Different thicknesses of titanium dioxide (TiO2) nanofilm were coated around the tapered fiber precisely and uniformly under different deposition cycles. Attributed to the higher refractive index of the TiO2 nanofilm compared to that of silica, an asymmetric Fabry\u2013Perot (F-P) resonator could be constructed along the fiber taper. The central wavelength of the F-P resonator could be controlled by adjusting the thickness of the TiO2 nanofilm. Such a F-P resonator is sensitive to changes in the surrounding refractive index (SRI), which is utilized to realize a high sensitivity refractometer. The refractometer developed by depositing 50.9-nm-thickness TiO2 on the tapered fiber shows SRI sensitivity as high as 7096 nm\/RIU in the SRI range of 1.3373\u20131.3500. Due to TiO2\u2019s advantages of high refractive index, lack of toxicity, and good biocompatibility, this refractometer is expected to have wide applications in the biochemical sensing field.<\/jats:p>","DOI":"10.3390\/s16081295","type":"journal-article","created":{"date-parts":[[2016,8,15]],"date-time":"2016-08-15T09:47:20Z","timestamp":1471254440000},"page":"1295","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["High Sensitivity Refractometer Based on TiO2-Coated Adiabatic Tapered Optical Fiber via ALD Technology"],"prefix":"10.3390","volume":"16","author":[{"given":"Shan","family":"Zhu","sequence":"first","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fufei","family":"Pang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sujuan","family":"Huang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fang","family":"Zou","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"},{"name":"Hebei GEO University, 136 East Huaian Road, Shijiazhuang 050031, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiang","family":"Guo","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianxiang","family":"Wen","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tingyun","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, 149 Yanchang Road, Shanghai 200072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,8,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1109\/50.983240","article-title":"Sensitivity characteristics of long-period fiber gratings","volume":"20","author":"Shu","year":"2002","journal-title":"J. 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