{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:51:34Z","timestamp":1760241094628,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,11,28]],"date-time":"2019-11-28T00:00:00Z","timestamp":1574899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61675032, 61875238, 61705260"],"award-info":[{"award-number":["61675032, 61875238, 61705260"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003399","name":"Science and Technology Commission of Shanghai Municipality","doi-asserted-by":"publisher","award":["SKLSFO2018-02"],"award-info":[{"award-number":["SKLSFO2018-02"]}],"id":[{"id":"10.13039\/501100003399","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shandong Provincial Natural Science Foundation of China","award":["ZR2016FM33"],"award-info":[{"award-number":["ZR2016FM33"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, a temperature self-compensated refractive index sensor based on fiber Bragg grating (FBG) and the ellipsoid structure is demonstrated. The ellipsoid can excite the cladding modes and recouple them into the fiber core. Two well-defined wavelength bands are observed in the reflection spectrum of the proposed sensor, i.e., the Bragg resonant peak and the cladding resonant peaks. By measuring the wavelength shift of the cladding resonant peak, the surrounding refractive index (SRI) can be determined, and the wavelength shift of the Bragg resonant peak can be used as a reliable reference to self-compensate the temperature variation (temperature sensitivity of 10.76 pm\/\u00b0C). When the SRI changes from 1.3352 to 1.3722, the cladding resonant peak redshifts linearly with an average sensitivity of 352.6 pm\/RIU (refractive index unit). When the SRI changes from 1.3722 to 1.4426, an exponential redshift is observed with a maximum sensitivity of 4182.2 pm\/RIU. Especially, the sensing performance is not very reliant on the distance between the FBG and the ellipsoid, greatly improving the ease of the fabrication.<\/jats:p>","DOI":"10.3390\/s19235211","type":"journal-article","created":{"date-parts":[[2019,11,28]],"date-time":"2019-11-28T08:14:04Z","timestamp":1574928844000},"page":"5211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Temperature Self-Compensated Refractive Index Sensor Based on Fiber Bragg Grating and the Ellipsoid Structure"],"prefix":"10.3390","volume":"19","author":[{"given":"Binbin","family":"Yan","sequence":"first","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Lei","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5929-6083","authenticated-orcid":false,"given":"Yanhua","family":"Luo","sequence":"additional","affiliation":[{"name":"Photonics &amp; Optical Communications, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney 2052, Australia"}]},{"given":"Liwei","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China"}]},{"given":"Haifeng","family":"Qi","sequence":"additional","affiliation":[{"name":"Laser Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}]},{"given":"Xiao","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Science, Minzu University of China, Beijing 100081 China"}]},{"given":"Kuiru","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Jinhui","family":"Yuan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Xinzhu","family":"Sang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Chang","family":"Wang","sequence":"additional","affiliation":[{"name":"Laser Institute, QiLu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}]},{"given":"Pengfei","family":"Lu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Gang-Ding","family":"Peng","sequence":"additional","affiliation":[{"name":"Photonics &amp; Optical Communications, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney 2052, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1063\/1.3115029","article-title":"Tapered fiber Mach-Zehnder interferometer for simultaneous measurement of refractive index and temperature","volume":"94","author":"Lu","year":"2009","journal-title":"Appl. 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