{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,9,19]],"date-time":"2024-09-19T16:12:16Z","timestamp":1726762336703},"reference-count":66,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T00:00:00Z","timestamp":1617408000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004704","name":"National Research Council of Thailand","doi-asserted-by":"publisher","award":["NRCT5-RSA63002-05"],"id":[{"id":"10.13039\/501100004704","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"We theoretically explore the potential of Si3N4 on SiO2 waveguide platform toward a wideband spectroscopic detection around the optical wavelength of 2 \u03bcm. The design of Si3N4 on SiO2 waveguide architectures consisting of a Si3N4 slot waveguide for a wideband on-chip spectroscopic sensing around 2 \u03bcm, and a Si3N4 multi-mode interferometer (MMI)-based coupler for light coupling from classical strip waveguide into the identified Si3N4 slot waveguides over a wide spectral range are investigated. We found that a Si3N4 on SiO2 slot waveguide structure can be designed for using as optical interaction part over a spectral range of interest, and the MMI structure can be used to enable broadband optical coupling from a strip to the slot waveguide for wideband multi-gas on-chip spectroscopic sensing. Reasons for the operating spectral range of the system are discussed.<\/jats:p>","DOI":"10.3390\/s21072513","type":"journal-article","created":{"date-parts":[[2021,4,4]],"date-time":"2021-04-04T02:03:36Z","timestamp":1617501816000},"page":"2513","source":"Crossref","is-referenced-by-count":7,"title":["Design and Simulation Investigation of Si3N4 Photonics Circuits for Wideband On-Chip Optical Gas Sensing around 2 \u00b5m Optical Wavelength"],"prefix":"10.3390","volume":"21","author":[{"given":"Natnicha","family":"Koompai","sequence":"first","affiliation":[{"name":"Centre de Nanosciences et de Nanotechnologies, Universit\u00e9 Paris Sud, CNRS, Universit\u00e9 Paris Saclay, 91120 Palaiseau, France"},{"name":"Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand"}]},{"ORCID":"http:\/\/orcid.org\/0000-0001-9250-3956","authenticated-orcid":false,"given":"Papichaya","family":"Chaisakul","sequence":"additional","affiliation":[{"name":"Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand"}]},{"given":"Pichet","family":"Limsuwan","sequence":"additional","affiliation":[{"name":"Department of Physics, Faculty of Science, King Mongkut\u2019s Institute of Technology Ladkrabang, Bangkok 10520, Thailand"}]},{"given":"Xavier","family":"Le Roux","sequence":"additional","affiliation":[{"name":"Centre de Nanosciences et de Nanotechnologies, Universit\u00e9 Paris Sud, CNRS, Universit\u00e9 Paris Saclay, 91120 Palaiseau, France"}]},{"given":"Laurent","family":"Vivien","sequence":"additional","affiliation":[{"name":"Centre de Nanosciences et de Nanotechnologies, Universit\u00e9 Paris Sud, CNRS, Universit\u00e9 Paris Saclay, 91120 Palaiseau, France"}]},{"given":"Delphine","family":"Marris-Morini","sequence":"additional","affiliation":[{"name":"Centre de Nanosciences et de Nanotechnologies, Universit\u00e9 Paris Sud, CNRS, Universit\u00e9 Paris Saclay, 91120 Palaiseau, France"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"073003","DOI":"10.1088\/2040-8978\/18\/7\/073003","article-title":"Roadmap on silicon photonics","volume":"18","author":"Thomson","year":"2016","journal-title":"J. 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