{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T10:11:10Z","timestamp":1775729470364,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,7,27]],"date-time":"2017-07-27T00:00:00Z","timestamp":1501113600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We have experimentally demonstrated an optical fiber Mach-Zehnder interferometer (MZI) structure formed by a few-mode photonic crystal fiber (PCF) for curvature measurement and inscribed a fiber Bragg grating (FBG) in the PCF for the purpose of simultaneously measuring temperature. The structure consists of a PCF sandwiched between two multi-mode fibers (MMFs). Bending experimental results show that the proposed sensor has a sensitivity of \u22121.03 nm\/m\u22121 at a curvature range from 10 m\u22121 to 22.4 m\u22121, and the curvature sensitivity of the embedded FBG was \u22120.003 nm\/m\u22121. Temperature response experimental results showed that the MZI\u2019s wavelength, \u03bba, has a sensitivity of 60.3 pm\/\u00b0C, and the FBG\u2019s Bragg wavelength, \u03bbb, has sensitivity of 9.2 pm\/\u00b0C in the temperature range of 8 to 100 \u00b0C. As such, it can be used for simultaneous measurement of curvature and temperature over ranges of 10 m\u22121 to 22.4 m\u22121 and 8 \u00b0C to 100 \u00b0C, respectively. The results show that the embedded FBG can be a good indicator to compensate the varying ambient temperature during a curvature measurement.<\/jats:p>","DOI":"10.3390\/s17081725","type":"journal-article","created":{"date-parts":[[2017,7,27]],"date-time":"2017-07-27T11:28:40Z","timestamp":1501154920000},"page":"1725","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Curvature and Temperature Measurement Based on a Few-Mode PCF Formed M-Z-I and an Embedded FBG"],"prefix":"10.3390","volume":"17","author":[{"given":"Hui","family":"Liu","sequence":"first","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Hangzhou","family":"Yang","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"},{"name":"National Key Laboratory of Thermostructure Composite Materials, Northwestern Polytechnical University, Xi\u2019an 710072, China"}]},{"given":"Xueguang","family":"Qiao","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Yongqiang","family":"Wang","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Xiaochong","family":"Liu","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Thermostructure Composite Materials, Northwestern Polytechnical University, Xi\u2019an 710072, China"}]},{"given":"Yen-Sian","family":"Lee","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Kok-Sing","family":"Lim","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Harith","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2017,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6438","DOI":"10.1364\/OL.39.006438","article-title":"Thermal regenerated grating operation at temperature up to 1400 \u00b0C using new class of multimaterial glass based photosensitive fiber","volume":"39","author":"Hang","year":"2014","journal-title":"Opt. 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