{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T09:13:16Z","timestamp":1776417196541,"version":"3.51.2"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,18]],"date-time":"2018-01-18T00:00:00Z","timestamp":1516233600000},"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>A highly sensitive strain sensor based on a novel fiber in line Mach-Zehnder interferometer (MZI) was demonstrated experimentally. The MZI was realized by splicing a section of photonic crystal fiber (PCF) with the same length of thin core fiber (TCF) between two single mode fibers (SMFs). The fringe visibility of MZI can reach as high as 20 dB in air. In particular, the strain sensitivity of \u22121.95 pm\/\u03bc\u03b5 was achieved within a range from 0 to 4000 \u03bc\u03b5. Furthermore, the strain properties of different length of MZI was investigated. It was found that the sensitivity was weekly dependent on the length of MZI. The strain sensitivities corresponding to the MZI with 35 mm PCF, 40 mm PCF and 45 mm PCF at 1550 nm band were \u22121.78 pm\/\u03bc\u03b5, \u22121.73 pm\/\u03bc\u03b5 and \u22121.63 pm\/\u03bc\u03b5, respectively. Additionally, the sensor has advantages of simple fabrication, compact size and high sensitivity as well as good fringe visibility.<\/jats:p>","DOI":"10.3390\/s18010278","type":"journal-article","created":{"date-parts":[[2018,1,18]],"date-time":"2018-01-18T12:19:48Z","timestamp":1516277988000},"page":"278","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Highly Sensitive Strain Sensor Based on a Novel Mach-Zehnder Interferometer with TCF-PCF Structure"],"prefix":"10.3390","volume":"18","author":[{"given":"Xinran","family":"Dong","sequence":"first","affiliation":[{"name":"State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical Engineering, Central South University, 932 South Lushan Street, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haifeng","family":"Du","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical Engineering, Central South University, 932 South Lushan Street, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2501-0470","authenticated-orcid":false,"given":"Zhi","family":"Luo","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical Engineering, Central South University, 932 South Lushan Street, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ji\u2019an","family":"Duan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of High Performance Complex Manufacturing, College of Mechanical and Electrical Engineering, Central South University, 932 South Lushan Street, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5729","DOI":"10.3390\/s110605729","article-title":"Ultra-abrupt tapered fiber Mach-Zehnder interferometer sensors","volume":"11","author":"Li","year":"2011","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"171","DOI":"10.3390\/s8010171","article-title":"Chemical sensing sensitivity of long period grating sensor enhanced by colloidal gold nanoparticles","volume":"8","author":"Tang","year":"2008","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1016\/j.snb.2016.09.160","article-title":"Sensing characteristics of a MF-filled photonic crystal fiber Sagnac interferometer for magnetic field detecting","volume":"242","author":"Liu","year":"2016","journal-title":"Sens. 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