{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:16:38Z","timestamp":1760242598665,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,2]],"date-time":"2017-12-02T00:00:00Z","timestamp":1512172800000},"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>A Pound-Drever-Hall (PDH)-based mode-locked cavity-enhanced sensor system was developed using a distributed feedback diode laser centered at 1.53 \u00b5m as the laser source. Laser temperature scanning, bias control of the piezoelectric ceramic transducer (PZT) and proportional-integral-derivative (PID) feedback control of diode laser current were used to repetitively lock the laser modes to the cavity modes. A gas absorption spectrum was obtained by using a series of absorption data from the discrete mode-locked points. The 15 cm-long Fabry-Perot cavity was sealed using an enclosure with an inlet and outlet for gas pumping and a PZT for cavity length tuning. The performance of the sensor system was evaluated by conducting water vapor measurements. A linear relationship was observed between the measured absorption signal amplitude and the H2O concentration. A minimum detectable absorption coefficient of 1.5 \u00d7 10\u20138 cm\u20131 was achieved with an averaging time of 700 s. This technique can also be used for the detection of other trace gas species by targeting the corresponding gas absorption line.<\/jats:p>","DOI":"10.3390\/s17122792","type":"journal-article","created":{"date-parts":[[2017,12,4]],"date-time":"2017-12-04T11:16:38Z","timestamp":1512386198000},"page":"2792","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Repetitively Mode-Locked Cavity-Enhanced Absorption Spectroscopy (RML-CEAS) for Near-Infrared Gas Sensing"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9401-3042","authenticated-orcid":false,"given":"Qixin","family":"He","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA"},{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5151-9409","authenticated-orcid":false,"given":"Minhan","family":"Lou","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chuantao","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA"},{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8328-1658","authenticated-orcid":false,"given":"Weilin","family":"Ye","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA"},{"name":"College of Engineering, Shantou University, 243 Daxue Road, Shantou 515063, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yiding","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2245-7565","authenticated-orcid":false,"given":"Frank","family":"Tittel","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"879","DOI":"10.1007\/s00340-010-4259-4","article-title":"A quantum cascade laser-based optical feedback cavity-enhanced absorption spectrometer for the simultaneous measurement of CH4 and N2O in air","volume":"102","author":"Hamilton","year":"2011","journal-title":"Appl. Phys. B"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"011106","DOI":"10.1063\/1.4939452","article-title":"Compact CH4 sensor system based on a continuous-wave, low power consumption, room temperature interband cascade laser","volume":"108","author":"Dong","year":"2016","journal-title":"Appl. Phys. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"10391","DOI":"10.1364\/OE.24.010391","article-title":"CW EC-QCL-based sensor for simultaneous detection of H2O, HDO, N2O and CH4 using multi-pass absorption spectroscopy","volume":"24","author":"Yu","year":"2016","journal-title":"Opt. Express"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1007\/s00340-016-6502-0","article-title":"Optical-feedback cavity-enhanced absorption spectroscopy with an interband cascade laser: Application to SO2 trace analysis","volume":"122","author":"Richard","year":"2016","journal-title":"Appl. Phys. B"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"6881","DOI":"10.1021\/acs.analchem.5b01341","article-title":"Cavity-Enhanced Near-Infrared Laser Absorption Spectrometer for the Measurement of Acetonitrile in Breath","volume":"87","author":"Gianella","year":"2015","journal-title":"Anal. Chem."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1007\/s00340-005-1828-z","article-title":"Fast, low-noise, mode-by-mode, cavity-enhanced absorption spectroscopy by diode-laser self-locking","volume":"80","author":"Morville","year":"2005","journal-title":"Appl. Phys. B"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"659","DOI":"10.1007\/s00340-006-2177-2","article-title":"Optical\u2013feedback cavity\u2013enhanced absorption: A compact spectrometer for real\u2013time measurement of atmospheric methane","volume":"83","author":"Romanini","year":"2006","journal-title":"Appl. Phys. B"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"974","DOI":"10.1364\/OL.41.000974","article-title":"Self-referenced, accurate and sensitive optical frequency comb spectroscopy with a virtually imaged phased array spectrometer","volume":"41","author":"Kowzan","year":"2016","journal-title":"Opt. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5277","DOI":"10.1364\/OL.39.005277","article-title":"Design of cavity-enhanced absorption cell for reducing transit-time broadening","volume":"39","author":"Abe","year":"2014","journal-title":"Opt. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"8766","DOI":"10.1364\/AO.54.008766","article-title":"Shock-tube measurements of exciter oxygen atoms using cavity-enhanced absorption spectroscopy","volume":"54","author":"Nation","year":"2015","journal-title":"Appl. Opt."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"4560","DOI":"10.1364\/OL.40.004560","article-title":"Real-time multiplexed digital cavity-enhanced spectroscopy","volume":"40","author":"Boyson","year":"2015","journal-title":"Opt. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1039\/B811793D","article-title":"Optical feedback cavity enhanced absorption spectroscopy with diode lasers","volume":"134","author":"Baran","year":"2009","journal-title":"Analyst"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"15013","DOI":"10.1364\/OE.16.015013","article-title":"Cavity enhanced absorption spectroscopy using a broadband prism cavity and a supercontinuum source","volume":"16","author":"Johnston","year":"2008","journal-title":"Opt. Express"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"A781","DOI":"10.1364\/OE.24.00A781","article-title":"Sensing atmospheric reactive species using light emitting diode by incoherent broadband cavity enhanced absorption spectroscopy","volume":"24","author":"Yi","year":"2016","journal-title":"Opt. Express"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"A536","DOI":"10.1364\/OE.24.00A536","article-title":"Sensitive CH4 detection applying quantum cascade laser based optical feedback cavity-enhanced absorption spectroscopy","volume":"24","author":"Zimmermann","year":"2016","journal-title":"Opt. Express"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"113027","DOI":"10.1088\/1367-2630\/18\/11\/113027","article-title":"Detection of HO2 in an atmospheric pressure plasma jet using optical feedback cavity-enhanced absorption spectroscopy","volume":"18","author":"Gianella","year":"2016","journal-title":"New J. Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1016\/j.jqsrt.2015.08.014","article-title":"High pressure Cavity Ring Down Spectroscopy: Application to the absorption continuum of CO2 near 1.7 \u00b5m","volume":"167","author":"Kassi","year":"2015","journal-title":"Quant. Spectrosc. Radiat. Transfer"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"E16","DOI":"10.1364\/AO.56.000E16","article-title":"Development of an incoherent broad-band cavity-enhanced aerosol extinction spectrometer and its application to measurement of aerosol optical hygroscopicity","volume":"56","author":"Zhao","year":"2017","journal-title":"Appl. Opt."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"890","DOI":"10.1021\/es0716913","article-title":"Incoherent broadband cavity-enhanced absorption spectroscopy in the near-ultraviolet: Application to HONO and NO2","volume":"42","author":"Gherman","year":"2007","journal-title":"Environ. Sci. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"755","DOI":"10.1007\/s00340-002-1032-3","article-title":"Off-axis continuous-wave cavity-enhanced absorption spectroscopy of narrow-band and broadband absorbers using red diode lasers","volume":"75","author":"Kasyutich","year":"2002","journal-title":"Appl. Phys. B"},{"key":"ref_21","first-page":"10446","article-title":"Fast in situ airborne measurement of ammonia using a mid-infrared off-axis ICOS spectrometer","volume":"47","author":"Leen","year":"2013","journal-title":"Environ. Sci. Technol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"6277","DOI":"10.1364\/OE.23.006277","article-title":"External cavity diode laser-based detection of trace gases with NICE-OHMS using current modulation","volume":"23","author":"Centeno","year":"2015","journal-title":"Opt. Express"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1007\/s00340-008-3126-z","article-title":"Noise-immune cavity-enhanced optical heterodyne molecular spectroscopy: Current status and future potential","volume":"92","author":"Foltynowicz","year":"2008","journal-title":"Appl. Phys. B"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1119\/1.1286663","article-title":"An introduction to Pound\u2013Drever\u2013Hall laser frequency stabilization","volume":"69","author":"Black","year":"2001","journal-title":"Am. J. Phys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"10178","DOI":"10.1364\/OE.16.010178","article-title":"Cavity enhanced absorption spectroscopy of multiple trace gas species using a supercontinuum radiation source","volume":"16","author":"Langridge","year":"2008","journal-title":"Opt. Express"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"063107","DOI":"10.1063\/1.3595680","article-title":"Pound-Drever-Hall-locked, frequency-stabilized cavity ring-down spectrometer","volume":"82","author":"Cygan","year":"2011","journal-title":"Rev. Sci. Instrum."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1007\/BF00702605","article-title":"Laser phase and frequency stabilization using an optical resonator","volume":"31","author":"Drever","year":"1983","journal-title":"Appl. Phys. B"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/j.snb.2016.12.146","article-title":"Development and field deployment of a mid-infrared methane sensor without pressure control using interband cascade laser absorption spectroscopy","volume":"244","author":"Zheng","year":"2017","journal-title":"Sens. Actuators B Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1312","DOI":"10.1109\/PROC.1966.5119","article-title":"Laser beams and resonators","volume":"54","author":"Kogelnik","year":"1966","journal-title":"Proc. IEEE"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1016\/j.jqsrt.2013.07.002","article-title":"The HITRAN2012 molecular spectroscopic database","volume":"130","author":"Rothman","year":"2013","journal-title":"J. Quant. Spectrosc. Radiat. Transf."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/12\/2792\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:52:20Z","timestamp":1760208740000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/12\/2792"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,12,2]]},"references-count":30,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2017,12]]}},"alternative-id":["s17122792"],"URL":"https:\/\/doi.org\/10.3390\/s17122792","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2017,12,2]]}}}