Super tiny quartz-tuning-fork-based light-induced thermoelastic spectroscopy sensing

Abstract

In this Letter, a sensitive light-induced thermoelastic spectroscopy (LITES)-based trace gas sensor by exploiting a super tiny quartz tuning fork (QTF) was demonstrated. The prong length and width of this QTF are 3500 µm and 90 µm, respectively, which determines a resonant frequency of 6.5 kHz. The low resonant frequency is beneficial to increase the energy accumulation time in a LITES sensor. The geometric dimension of QTF on the micrometer scale is advantageous to obtain a great thermal expansion and thus can produce a strong piezoelectric signal. The temperature gradient distribution of the super tiny QTF was simulated based on the finite element analysis and is higher than that of the commercial QTF with 32.768 kHz. Acetylene (C2H2) was used as the analyte. Under the same conditions, the use of the super tiny QTF achieved a 1.64-times signal improvement compared with the commercial QTF. The system shows excellent long-term stability according to the Allan deviation analysis, and a minimum detection limit (MDL) would reach 190 ppb with an integration time of 220 s.

Development of 1.6‐μm Er: YAG solid‐state laser for lidar

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“…In view of the advantages of 1.6‐μm band laser, it has important applications in the fields of laser radar, industry, military, gas sensing, and optical communication 4–7 . For example, in the military, a 1.6‐μm laser has excellent stable performance under different atmospheric conditions.…”

Miniaturized methane detection system based on photoacoustic spectroscopy

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Performance Characterization of a Fully Transportable Mid-Infrared Laser Heterodyne Radiometer (LHR)

“…Measurement of the vertical concentration profiles of atmospheric trace gases is very important for understanding the physics, chemistry, dynamics, and radiation budget of the atmosphere as well as validating chemical models and satellite observations [ 1 , 2 , 3 , 4 ]. Laser heterodyne radiometer (LHR), as a kind of passive remote sensing technology, was introduced and developed in the 1970s to meet the needs of observing the ozone hole in the atmosphere [ 5 , 6 , 7 ].…”