{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T21:36:05Z","timestamp":1774388165433,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2011,5,27]],"date-time":"2011-05-27T00:00:00Z","timestamp":1306454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A fiber inline Mach-Zehnder interferometer (MZI) consisting of ultra-abrupt fiber tapers was fabricated through a new fusion-splicing method. By fusion-splicing, the taper diameter-length ratio is around 1:1, which is much greater than those (1:10) made by stretching. The proposed fabrication method is very low cost, 1\/20\u20131\/50 of those of LPFG pair MZI sensors. The fabricated MZIs are applied to measure refractive index, temperature and rotation angle changes. The temperature sensitivity of the MZI at a length of 30 mm is 0.061 nm\/\u00b0C from 30\u2013350 \u00b0C. The proposed MZI is also used to measure rotation angles ranging from 0\u00b0 to 0.55\u00b0; the sensitivity is 54.98 nm\/\u00b0. The refractive index sensitivity is improved by 3\u20135 fold by fabricating an inline micro\u2013trench on the fiber cladding using a femtosecond laser. Acetone vapor of 50 ppm in N2 is tested by the MZI sensor coated with MFI\u2013type zeolite thin film. The proposed MZI sensors are capable of in situ detection in many areas of interest such as environmental management, industrial process control, and public health.<\/jats:p>","DOI":"10.3390\/s110605729","type":"journal-article","created":{"date-parts":[[2011,5,27]],"date-time":"2011-05-27T10:58:12Z","timestamp":1306493892000},"page":"5729-5739","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":65,"title":["Ultra-Abrupt Tapered Fiber Mach-Zehnder Interferometer Sensors"],"prefix":"10.3390","volume":"11","author":[{"given":"Benye","family":"Li","sequence":"first","affiliation":[{"name":"School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lan","family":"Jiang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China"},{"name":"Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sumei","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lanying","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Mechanical Engineering, Beijing Institute of Technology, Beijing, 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai-Lung","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, MO 65409, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R49","DOI":"10.1088\/0957-0233\/14\/5\/201","article-title":"Optical fiber long-period grating sensors: Characteristics and application","volume":"14","author":"James","year":"2003","journal-title":"Meas. 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