We present an all-fiber-based laser gas analyzer (LGA) employing quartz-enhanced photoacoustic spectroscopy (QEPAS) and a side-polished fiber (SPF). The LGA comprises a custom quartz tuning fork (QTF) with 0.8 mm prong spacing, two acoustic micro-resonators (mR) located on either side of the prong spacing, and a single-mode fiber containing a 17 mm polished section passing through both mRs and QTF. The SPF polished face is positioned to enable the evanescent wave (EW) to create a photoacoustic wave and excite the fundamental flexural mode of the QTF. Sensor performance was demonstrated using methane in nitrogen gas mixtures, with CH mixing ratios ranging from 75 ppmv to 1% (by volume), measured with an accumulation time of 300 ms, and a minimum detection limit of 34 ppmv subsequently determined. The EW-QEPAS sensor is ideal for miniaturization, as it does not contain any free-space optics and is suitable for gas sensing in harsh environments and where mobility is required.
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http://dx.doi.org/10.1016/j.pacs.2024.100586 | DOI Listing |
We demonstrate the heterogeneous integration of GaInAsSb-GaSb photodiodes on 220 nm SOI photonic integrated circuits (PICs) using the micro-transfer-printing (μTP) technology, for operation in the short-wave infrared (SWIR) wavelength region. Utilizing an evanescent coupling scheme between a silicon waveguide and a III-V structure, the device exhibits a room temperature responsivity of 1.23 and 1.
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View Article and Find Full Text PDFPhotoacoustics
April 2024
Centre for Advanced Photonics and Process Analysis, Munster Technological University, Cork, T12 P928, Ireland.
We present an all-fiber-based laser gas analyzer (LGA) employing quartz-enhanced photoacoustic spectroscopy (QEPAS) and a side-polished fiber (SPF). The LGA comprises a custom quartz tuning fork (QTF) with 0.8 mm prong spacing, two acoustic micro-resonators (mR) located on either side of the prong spacing, and a single-mode fiber containing a 17 mm polished section passing through both mRs and QTF.
View Article and Find Full Text PDFBiosens Bioelectron
March 2025
School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, 300072, China.
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