20.500.12556/DKUM-90318 Gas sensing system based on an all-fiber photothermal microcell This article presents an all-fiber, miniature Fabry-Perot gas sensor based on photothermal absorption spectroscopy with a custom-made and cost-efficient interrogation system. The sensing gas microcell has a diameter of 125 μ m and a length of 1 mm, and allows for free gas exchange within the optical resonator through micromachined slits. High light intensity and confinement are ensured by delivering the excitation light directly into the gas microcell through a lead-in single-mode fiber. This enhances the photothermal effect and provides a short system response time. The interrogation system utilizes the modulation of an excitation laser diode with a fixed frequency while locking the probe laser onto the gas microcell’s quadrature point (QP) and observing the variations of the reflected optical power. To show the potential of the proposed system, nitrogen dioxide (NO2 was measured in dry air. Thereby, a limit of detection of 20 ppm could be achieved for 10 s integration time. Furthermore, the small dimensions of the sensor allow for improved dynamic performance with photothermal modulation frequencies as high as 7 kHz. Fabry–Perot interferometer FPI fiber gas cell fiber gas sensor nitrogen dioxide NO2 photothermal effect interferoemtri plinske celice sensorji true false true IEEE XPLORE Angleški jezik Slovenski jezik https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=7361 © 2024 The Authors Članek v reviji 2024-08-29 08:47:14 2024-08-29 08:47:15 2026-01-06 11:39:47 0000-00-00 00:00:00 2024 0 0 str. 19125-19135 no. 12 Vol. 24 May 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2024-02-22 2024-04-22 2024-05-03 535 199219459 10.1109/JSEN.2024.3394651 1530-437X Gas_Sensing_System_Based_on_an_All-Fiber_Photothermal_Microcell.pdf Gas_Sensing_System_Based_on_an_All-Fiber_Photothermal_Microcell.pdf 1 9DC7BDF8647C5A43B6AB0F32A815A519 c421747cb78d68e502c667a304c9b2d592896cb9b7674b8c85d78bad5e56ed3f 61858361-65d3-11ef-8608-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=183665 https://ieeexplore.ieee.org/document/10520167 0 05165aac-eaec-11f0-a407-00155d580e02 https://dk.um.si/Dokument.php?lang=slv&id=201787 Fakulteta za elektrotehniko, računalništvo in informatiko 0 0 0