{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T07:52:48Z","timestamp":1774857168158,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,17]],"date-time":"2018-04-17T00:00:00Z","timestamp":1523923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China (NSFC)","award":["Grant No. 61435006, 61525502, 61705046, 61705088"],"award-info":[{"award-number":["Grant No. 61435006, 61525502, 61705046, 61705088"]}]},{"name":"National High Technology 863 Research and 377 Development Program of China","award":["No. 2015AA015501, 20615010, 20916003"],"award-info":[{"award-number":["No. 2015AA015501, 20615010, 20916003"]}]},{"name":"Guangdong Science and 378 Technology Planning Projects of China","award":["No. 2014B050505020, 2015B010114007 and 2014B090904045"],"award-info":[{"award-number":["No. 2014B050505020, 2015B010114007 and 2014B090904045"]}]},{"name":"Guangzhou Science and Technology Project of Guangdong Province, China","award":["No. 201604016095 and 201604030027"],"award-info":[{"award-number":["No. 201604016095 and 201604030027"]}]},{"name":"China Postdoctoral Scientific Foundation","award":["No. 2017M612608"],"award-info":[{"award-number":["No. 2017M612608"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A liquid-filled D-shaped fiber (DF) cavity serving as an in-fiber Mach\u2013Zehnder interferometer (MZI) has been proposed and experimentally demonstrated for temperature sensing with ultrahigh sensitivity. The miniature MZI is constructed by splicing a segment of DF between two single-mode fibers (SMFs) to form a microcavity (MC) for filling and replacement of various refractive index (RI) liquids. By adjusting the effective RI difference between the DF and MC (the two interference arms), experimental and calculated results indicate that the interference spectra show different degrees of temperature dependence. As the effective RI of the liquid-filled MC approaches that of the DF, temperature sensitivity up to \u221284.72 nm\/\u00b0C with a linear correlation coefficient of 0.9953 has been experimentally achieved for a device with the MC length of 456 \u03bcm, filled with liquid RI of 1.482. Apart from ultrahigh sensitivity, the proposed MCMZI device possesses additional advantages of its miniature size and simple configuration; these features make it promising and competitive in various temperature sensing applications, such as consumer electronics, biological treatments, and medical diagnosis.<\/jats:p>","DOI":"10.3390\/s18041239","type":"journal-article","created":{"date-parts":[[2018,4,18]],"date-time":"2018-04-18T03:51:13Z","timestamp":1524023473000},"page":"1239","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Ultrasensitive Mach-Zehnder Interferometric Temperature Sensor Based on Liquid-Filled D-Shaped Fiber Cavity"],"prefix":"10.3390","volume":"18","author":[{"given":"Hui","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shecheng","family":"Gao","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunhan","family":"Luo","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4299-3760","authenticated-orcid":false,"given":"Zhenshi","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Songsong","family":"Xiong","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Optoelectronic Materials and Technologies and School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Wan","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xincheng","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bingsen","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanhua","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miao","family":"He","sequence":"additional","affiliation":[{"name":"School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weiping","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, College of Information Science and Technology, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhe","family":"Chen","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhaohui","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Optoelectronic Materials and Technologies and School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1016\/S1068-5200(02)00527-8","article-title":"Review of the present status of optical fiber sensors","volume":"9","author":"Lee","year":"2003","journal-title":"Opt. 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