{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:50:35Z","timestamp":1760151035092,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,16]],"date-time":"2022-02-16T00:00:00Z","timestamp":1644969600000},"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>The impact of airborne molecular contaminants (AMCs) on the lifetime of fused silica UV optics in high power lasers (HPLs) is a critical issue. In this work, we demonstrated the on-line monitoring method of AMCs concentration based on the Sagnac microfiber structure. In the experiment, a Sagnac microfiber loop with mesoporous silica coating was fabricated by the microheater brushing technique and dip coating. The physical absorption of AMCs in the mesoporous coating results in modification of the surrounding refractive index (RI). By monitoring the spectral shift in the wavelength domain, the proposed structure can operate as an AMCs concentration sensor. The sensitivity of the AMCs sensor can achieve 0.11 nm (mg\/m3). By evaluating the gas discharge characteristic of four different low volatilization greases in a coarse vacuum environment, we demonstrated the feasibility of the proposed sensors. The use of these sensors was shown to be very promising for meeting the requirements of detecting trace amounts of contaminants.<\/jats:p>","DOI":"10.3390\/s22041520","type":"journal-article","created":{"date-parts":[[2022,2,16]],"date-time":"2022-02-16T21:36:24Z","timestamp":1645047384000},"page":"1520","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Novel Airborne Molecular Contaminants Sensor Based on Sagnac Microfiber Structure"],"prefix":"10.3390","volume":"22","author":[{"given":"Guorui","family":"Zhou","sequence":"first","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siheng","family":"Xiang","sequence":"additional","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"You","sequence":"additional","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunling","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Longfei","family":"Niu","sequence":"additional","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yilan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinxiang","family":"Miao","sequence":"additional","affiliation":[{"name":"Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiufang","family":"Xie","sequence":"additional","affiliation":[{"name":"Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang 621900, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"18703","DOI":"10.1364\/OE.17.018703","article-title":"Impact of storage induced outgassing organic contamination on laser induced damage of silica optics at 351 nm","volume":"17","author":"Belin","year":"2009","journal-title":"Opt. 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