{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,1]],"date-time":"2025-11-01T05:46:39Z","timestamp":1761975999198,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,6,30]],"date-time":"2022-06-30T00:00:00Z","timestamp":1656547200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"],"award-info":[{"award-number":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"]}]},{"name":"Key R &amp; D of Jilin Provincial Department of Science and Technology-key Industrial Core Technology Research Project","award":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"],"award-info":[{"award-number":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"]}]},{"name":"Basic and Applied Basic Research Foundation of Guangdong Province","award":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"],"award-info":[{"award-number":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"]}]},{"name":"State Key Laboratory of Applied Optics","award":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"],"award-info":[{"award-number":["No. 62005101","No. 51905155","20210201091GX","No. 2022A1515010235","No. SKLAO2021001A03"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Herein, a broadband ultrasensitive acoustic sensor based on an optical nanofiber coupler (ONC) attached to a diaphragm is designed and experimentally demonstrated. The ONC is sensitive to axial strain and works as the core transducing element to monitor the deformation of the diaphragm driven by acoustic waves. We first theoretically studied the sensing property of the ONC to axial strain and the deformation of the diaphragm. The results reveal that ONC working at the dispersion turning point (DTP) shows improved ultra-sensitivity towards axial strain, and the largest deformation of the circular diaphragm occurs at the center. Guided by the theoretical results, we fabricated an ONC with a DPT at 1550 nm, and we fixed one end of the ONC to the center of the diaphragm and the other end to the edge to construct the acoustic sensor. Finally, the experimental results show that the sensor can achieve accurate measurement in the broadband acoustic wave range of 30~20,000 Hz with good linearity. Specifically, when the input acoustic wave frequency is 120 Hz, the sensitivity reaches 1923 mV\/Pa, the signal-to-noise ratio is 42.45 dB, and the minimum detectable sound pressure is 330 \u03bcPa\/Hz1\/2. The sensor has the merits of simple structure, low cost, and high performance, and it provides a new method for acoustic wave detection.<\/jats:p>","DOI":"10.3390\/s22134940","type":"journal-article","created":{"date-parts":[[2022,7,1]],"date-time":"2022-07-01T01:40:36Z","timestamp":1656639636000},"page":"4940","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Broadband Acoustic Sensing with Optical Nanofiber Couplers Working at the Dispersion Turning Point"],"prefix":"10.3390","volume":"22","author":[{"given":"Xu","family":"Gao","sequence":"first","affiliation":[{"name":"College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130000, China"},{"name":"School of Opto-Electronic Engineering, Changchun University of Science and Technology, Changchun 130022, China"}]},{"given":"Jiajie","family":"Wen","sequence":"additional","affiliation":[{"name":"School of Opto-Electronic Engineering, Changchun University of Science and Technology, Changchun 130022, China"}]},{"given":"Jiajia","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Agricultural Equipment Engineering, Henan University of Science and Technology, Luoyang 471003, China"}]},{"given":"Kaiwei","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Bionic Engineering of Ministry of Education, Jilin University, Changchun 130022, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1007\/s13320-014-0148-5","article-title":"Advanced fiber-optic acoustic sensors","volume":"4","author":"Teixeira","year":"2014","journal-title":"Photonic Sens."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4377","DOI":"10.1109\/JLT.2015.2464306","article-title":"Highly Sensitive Phase-Front-Modulation Fiber Acoustic Sensor","volume":"33","author":"Jo","year":"2015","journal-title":"J. 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Actuators A Phys."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/13\/4940\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:40:55Z","timestamp":1760139655000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/13\/4940"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,6,30]]},"references-count":18,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2022,7]]}},"alternative-id":["s22134940"],"URL":"https:\/\/doi.org\/10.3390\/s22134940","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,6,30]]}}}