{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:34:55Z","timestamp":1760232895264,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,12,2]],"date-time":"2022-12-02T00:00:00Z","timestamp":1669939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"],"award-info":[{"award-number":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"],"award-info":[{"award-number":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003399","name":"the Key Project of Science and Technology Commission of Shanghai Municipality","doi-asserted-by":"publisher","award":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"],"award-info":[{"award-number":["12174107","11874060","61991444","11933005","11734009","2019YFA0705000","21DZ1101500"]}],"id":[{"id":"10.13039\/501100003399","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We propose a hybrid laser microfabrication approach for the manufacture of three-dimensional (3D) optofluidic spot-size converters in fused silica glass by a combination of femtosecond (fs) laser microfabrication and carbon dioxide laser irradiation. Spatially shaped fs laser-assisted chemical etching was first performed to form 3D hollow microchannels in glass, which were composed of embedded straight channels, tapered channels, and vertical channels connected to the glass surface. Then, carbon dioxide laser-induced thermal reflow was carried out for the internal polishing of the whole microchannels and sealing parts of the vertical channels. Finally, 3D optofluidic spot-size converters (SSC) were formed by filling a liquid-core waveguide solution into laser-polished microchannels. With a fabricated SSC structure, the mode spot size of the optofluidic waveguide was expanded from ~8 \u03bcm to ~23 \u03bcm with a conversion efficiency of ~84.1%. Further measurement of the waveguide-to-waveguide coupling devices in the glass showed that the total insertion loss of two symmetric SSC structures through two ~50 \u03bcm-diameter coupling ports was ~6.73 dB at 1310 nm, which was only about half that of non-SSC structures with diameters of ~9 \u03bcm at the same coupling distance. The proposed approach holds great potential for developing novel 3D fluid-based photonic devices for mode conversion, optical manipulation, and lab-on-a-chip sensing.<\/jats:p>","DOI":"10.3390\/s22239449","type":"journal-article","created":{"date-parts":[[2022,12,5]],"date-time":"2022-12-05T08:10:57Z","timestamp":1670227857000},"page":"9449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Manufacture of Three-Dimensional Optofluidic Spot-Size Converters in Fused Silica Using Hybrid Laser Microfabrication"],"prefix":"10.3390","volume":"22","author":[{"given":"Jianping","family":"Yu","sequence":"first","affiliation":[{"name":"School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"},{"name":"Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China"},{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Jian","family":"Xu","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"},{"name":"Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Aodong","family":"Zhang","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Yunpeng","family":"Song","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Jia","family":"Qi","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Qiaonan","family":"Dong","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China"},{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Jianfang","family":"Chen","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China"}]},{"given":"Zhaoxiang","family":"Liu","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"given":"Wei","family":"Chen","sequence":"additional","affiliation":[{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8269-5907","authenticated-orcid":false,"given":"Ya","family":"Cheng","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China"},{"name":"XXL\u2014The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3013","DOI":"10.1364\/OL.41.003013","article-title":"Broadband fiber-chip zero-order surface grating coupler with 0.4 dB efficiency","volume":"41","author":"Cheben","year":"2016","journal-title":"Opt. 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