{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,31]],"date-time":"2025-10-31T16:54:32Z","timestamp":1761929672252,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2013,8,5]],"date-time":"2013-08-05T00:00:00Z","timestamp":1375660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This article describes a gas monitoring system for detecting nitrous oxide (N2O) gas using a compact mid-infrared laser source based on difference-frequency generation in a quasi-phase-matched LiNbO3 waveguide. We obtained a stable output power of 0.62 mW from a 4.6-\u03bcm-band continuous-wave laser source operating at room temperature. This laser source enabled us to detect atmospheric N2O gas at a concentration as low as 35 parts per billion. Using this laser source, we constructed a new real-time in-situ monitoring system for detecting N2O gas emitted from potted plants. A few weeks of monitoring with the developed detection system revealed a strong relationship between nitrogen fertilization and N2O emission. This system is promising for the in-situ long-term monitoring of N2O in agricultural production, and it is also applicable to the detection of other greenhouse gases.<\/jats:p>","DOI":"10.3390\/s130809999","type":"journal-article","created":{"date-parts":[[2013,8,5]],"date-time":"2013-08-05T12:16:02Z","timestamp":1375704962000},"page":"9999-10013","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Real-Time N2O Gas Detection System for Agricultural Production Using a 4.6-\u00b5m-Band Laser Source Based on a Periodically Poled LiNbO3 Ridge Waveguide"],"prefix":"10.3390","volume":"13","author":[{"given":"Akio","family":"Tokura","sequence":"first","affiliation":[{"name":"NTT Photonics Laboratories, Nippon Telegraph and Telephone Corporation, 3-1,  Morinosato Wakamiya, Atsugi-shi, Kanagawa Pref. 243-0198, Japan"}]},{"given":"Masaki","family":"Asobe","sequence":"additional","affiliation":[{"name":"NTT Photonics Laboratories, Nippon Telegraph and Telephone Corporation, 3-1,  Morinosato Wakamiya, Atsugi-shi, Kanagawa Pref. 243-0198, Japan"}]},{"given":"Koji","family":"Enbutsu","sequence":"additional","affiliation":[{"name":"NTT Photonics Laboratories, Nippon Telegraph and Telephone Corporation, 3-1,  Morinosato Wakamiya, Atsugi-shi, Kanagawa Pref. 243-0198, Japan"}]},{"given":"Toshihiro","family":"Yoshihara","sequence":"additional","affiliation":[{"name":"Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko-shi, Chiba Pref. 270-1194, Japan"}]},{"given":"Shin-nosuke","family":"Hashida","sequence":"additional","affiliation":[{"name":"Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko-shi, Chiba Pref. 270-1194, Japan"}]},{"given":"Hirokazu","family":"Takenouchi","sequence":"additional","affiliation":[{"name":"NTT Photonics Laboratories, Nippon Telegraph and Telephone Corporation, 3-1,  Morinosato Wakamiya, Atsugi-shi, Kanagawa Pref. 243-0198, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2013,8,5]]},"reference":[{"key":"ref_1","unstructured":"National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory Global Monitoring Division. 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