{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T20:59:37Z","timestamp":1775854777939,"version":"3.50.1"},"reference-count":72,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,20]],"date-time":"2020-11-20T00:00:00Z","timestamp":1605830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001665","name":"Agence Nationale de la Recherche","doi-asserted-by":"publisher","award":["ANR-11-ASTR-0027"],"award-info":[{"award-number":["ANR-11-ASTR-0027"]}],"id":[{"id":"10.13039\/501100001665","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001665","name":"Agence Nationale de la Recherche","doi-asserted-by":"publisher","award":["ANR-11-ECOT-0004"],"award-info":[{"award-number":["ANR-11-ECOT-0004"]}],"id":[{"id":"10.13039\/501100001665","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001665","name":"Agence Nationale de la Recherche","doi-asserted-by":"publisher","award":["ANR-12-ASTR-0028"],"award-info":[{"award-number":["ANR-12-ASTR-0028"]}],"id":[{"id":"10.13039\/501100001665","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Spectroscopic techniques based on Distributed FeedBack (DFB) Quantum Cascade Lasers (QCL) provide good results for gas detection in the mid-infrared region in terms of sensibility and selectivity. The main limitation is the QCL relatively low tuning range (~10 cm\u22121) that prevents from monitoring complex species with broad absorption spectra in the infrared region or performing multi-gas sensing. To obtain a wider tuning range, the first solution presented in this paper consists of the use of a DFB QCL array. Tuning ranges from 1335 to 1387 cm\u22121 and from 2190 to 2220 cm\u22121 have been demonstrated. A more common technique that will be presented in a second part is to implement a Fabry\u2013Perot QCL chip in an external-cavity (EC) system so that the laser could be tuned on its whole gain curve. The use of an EC system also allows to perform Intra-Cavity Laser Absorption Spectroscopy, where the gas sample is placed within the laser resonator. Moreover, a technique only using the QCL compliance voltage technique can be used to retrieve the spectrum of the gas inside the cavity, thus no detector outside the cavity is needed. Finally, a specific scheme using an EC coherent QCL array can be developed. All these widely-tunable Quantum Cascade-based sources can be used to demonstrate the development of optical gas sensors.<\/jats:p>","DOI":"10.3390\/s20226650","type":"journal-article","created":{"date-parts":[[2020,11,20]],"date-time":"2020-11-20T09:46:18Z","timestamp":1605865578000},"page":"6650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Widely-Tunable Quantum Cascade-Based Sources for the Development of Optical Gas Sensors"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2997-2359","authenticated-orcid":false,"given":"Virginie","family":"Z\u00e9ninari","sequence":"first","affiliation":[{"name":"Unit\u00e9 Mixte de Recherche 7331, Groupe de Spectrom\u00e9trie Mol\u00e9culaire et Atmosph\u00e9rique, Centre National de la Recherche Scientifique, Universite\u0301 de Reims Champagne Ardenne, 51097 Reims, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rapha\u00ebl","family":"Vallon","sequence":"additional","affiliation":[{"name":"Unit\u00e9 Mixte de Recherche 7331, Groupe de Spectrom\u00e9trie Mol\u00e9culaire et Atmosph\u00e9rique, Centre National de la Recherche Scientifique, Universite\u0301 de Reims Champagne Ardenne, 51097 Reims, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laurent","family":"Bizet","sequence":"additional","affiliation":[{"name":"Unit\u00e9 Mixte de Recherche 7331, Groupe de Spectrom\u00e9trie Mol\u00e9culaire et Atmosph\u00e9rique, Centre National de la Recherche Scientifique, Universite\u0301 de Reims Champagne Ardenne, 51097 Reims, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cl\u00e9ment","family":"Jacquemin","sequence":"additional","affiliation":[{"name":"Unit\u00e9 Mixte de Recherche 7331, Groupe de Spectrom\u00e9trie Mol\u00e9culaire et Atmosph\u00e9rique, Centre National de la Recherche Scientifique, Universite\u0301 de Reims Champagne Ardenne, 51097 Reims, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guillaume","family":"Aoust","sequence":"additional","affiliation":[{"name":"mirSense, Centre d\u2019int\u00e9gration NanoINNOV, 91120 Palaiseau, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gr\u00e9gory","family":"Maisons","sequence":"additional","affiliation":[{"name":"mirSense, Centre d\u2019int\u00e9gration NanoINNOV, 91120 Palaiseau, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mathieu","family":"Carras","sequence":"additional","affiliation":[{"name":"mirSense, Centre d\u2019int\u00e9gration NanoINNOV, 91120 Palaiseau, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9682-2409","authenticated-orcid":false,"given":"Bertrand","family":"Parvitte","sequence":"additional","affiliation":[{"name":"Unit\u00e9 Mixte de Recherche 7331, Groupe de Spectrom\u00e9trie Mol\u00e9culaire et Atmosph\u00e9rique, Centre National de la Recherche Scientifique, Universite\u0301 de Reims Champagne Ardenne, 51097 Reims, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1126\/science.264.5158.553","article-title":"Quantum cascade laser","volume":"264","author":"Faist","year":"1994","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tittel, F.K., and Lewicki, R. 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