High-sensitivity miniature dual-resonance photoacoustic sensor based on silicon cantilever beam for trace gas sensing

High-Sensitivity Multitrace Gas Simultaneous Detection Based on an All-Optical Miniaturized Photoacoustic Sensor

“…When the integration time (IT) of the three VLIAs is 1 s, the deviations are 1.28, 1.52, and 1.19 pm for CH 4 , C 2 H 2 , and H 2 S, respectively, and based on the detection sensitivities of the gas sensor to CH 4 , C 2 H 2 , and H 2 S, the MDLs for CH 4 , C 2 H 2 , and H 2 S are estimated to be 167, 47.5, and 1597 ppb, respectively. The results of the Allan-Werle analysis − are shown in Figure a–c. When the three ITs are, respectively, 100 s, the corresponding MDLs are 16.6, 4.8, and 162 ppb for CH 4 , C 2 H 2 , and H 2 S. Table summarizes the performance parameters of previously developed sensors based on PAS for single trace gas (CH 4 , C 2 H 2 , and H 2 S) and multiple trace gas (CH 4 and C 2 H 2 ) detection as a comparison to demonstrate the performance of the designed all-optical miniaturized PA sensor.…”

Photothermal gas detection using a miniaturized fiber Fabry-Perot cavity

“…If these requirements are satisfied, the induced periodic perturbation of the thermodynamic equilibrium will result in localized gas expansion, that gives rise to an acoustic wave and simultaneously modulates the RI of the gas sample. In photoacoustic spectroscopy (PAS), the acoustic wave is commonly quantified using microphones or cantilevers (often in combination with acoustic resonators) and quartz tuning forks [22][23][24][25][26][27][28][29][30][31]. In contrast, a gas sensor that relies on the PT effect usually takes advantage of an interferometric optical setup, which enhances the sensitivity for measuring the induced the RI modulation.…”

Multi-mechanism collaboration enhanced photoacoustic analyzer for trace H2S detection

“…The nanocrystalline silicon-made cantilever has stable properties and excellent sound pressure response characteristics. For a rectangular silicon cantilever, the MR frequency can be expressed as [15] , [37] , [38] : Where E si and ρ si are Young's modulus and density of monocrystalline silicon, respectively. According to Eq.…”