{"title":"Sensor using a photo-acoustic absorption cell with two perpendicular acoustic resonators to analyze multiple molecules.","authors":"Ismail Bayrakli, Hatice Akman, Filiz Sari","doi":"10.1364/AO.495411","DOIUrl":null,"url":null,"abstract":"<p><p>An ultra-high sensitivity multi-molecule sensor based on a photo-acoustic cell with two perpendicular acoustic resonators and a common microphone has been reported. In this work, a 4.5 µm distributed-feedback quantum cascade laser and a 1.5 µm external cavity diode laser (EC-DL) were used as optical excitation sources. Considering the spectral ranges of the lasers used, it is possible to analyze eight molecules (<i>Q</i> <i>C</i> <i>L</i>:<i>N</i> <sub>2</sub> <i>O</i> and <i>C</i> <i>O</i> <sub>2</sub>, EC-DL: <i>H</i> <sub>2</sub> <i>O</i>, <i>H</i> <sub>2</sub> <i>S</i>, <i>N</i> <i>H</i> <sub>3</sub>, CO, <i>C</i> <i>H</i> <sub>4</sub>, and <i>C</i> <sub>2</sub> <i>H</i> <sub>2</sub>). The <i>N</i> <sub>2</sub> <i>O</i> molecule was used to evaluate the performance of the photo-acoustic spectroscopy (PAS)-based sensor. A sensitivity of 0.073 V/ppm and a linearity of 0.99 were found by analyzing the PAS signal as a function of <i>N</i> <sub>2</sub> <i>O</i> concentration at 2237.656<i>c</i> <i>m</i> <sup>-1</sup>. The long-term performance of the sensor was determined by performing an Allan deviation analysis. A minimum detection limit of 9.8 ppb for 90 s integration time was achieved. The simultaneous multi-trace gas detection capability was verified by measurement of <i>N</i> <sub>2</sub> <i>O</i>, <i>C</i> <i>O</i> <sub>2</sub>, and <i>H</i> <sub>2</sub> <i>O</i>. Depending on the coarse/fine-tuning ranges of the lasers used, the number of molecules analyzed can be further increased. Such a sensor could provide simultaneous diagnosis of many diseases through an analysis of breath air and simultaneous monitoring of the most important greenhouse gases.</p>","PeriodicalId":8092,"journal":{"name":"Applied optics","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied optics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1364/AO.495411","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"OPTICS","Score":null,"Total":0}
引用次数: 0
Abstract
An ultra-high sensitivity multi-molecule sensor based on a photo-acoustic cell with two perpendicular acoustic resonators and a common microphone has been reported. In this work, a 4.5 µm distributed-feedback quantum cascade laser and a 1.5 µm external cavity diode laser (EC-DL) were used as optical excitation sources. Considering the spectral ranges of the lasers used, it is possible to analyze eight molecules (QCL:N2O and CO2, EC-DL: H2O, H2S, NH3, CO, CH4, and C2H2). The N2O molecule was used to evaluate the performance of the photo-acoustic spectroscopy (PAS)-based sensor. A sensitivity of 0.073 V/ppm and a linearity of 0.99 were found by analyzing the PAS signal as a function of N2O concentration at 2237.656cm-1. The long-term performance of the sensor was determined by performing an Allan deviation analysis. A minimum detection limit of 9.8 ppb for 90 s integration time was achieved. The simultaneous multi-trace gas detection capability was verified by measurement of N2O, CO2, and H2O. Depending on the coarse/fine-tuning ranges of the lasers used, the number of molecules analyzed can be further increased. Such a sensor could provide simultaneous diagnosis of many diseases through an analysis of breath air and simultaneous monitoring of the most important greenhouse gases.
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A highly regarded, premium quality must read for everyone in the optics field that offers applications-centered research in optics, photonics, imaging, and sensing. Topics germane to the journal include optical technology, lasers, photonics, environmental optics, and information processing.