Water vapor concentration measurement in air using filament-induced fluorescence spectroscopy

Wang, Zhihui; Xu, Huailiang; Daigle, J.-F.; Sridharan, Aravindan; Yuan, Shuai; Chin, See Leang

doi:10.1364/ol.37.001706

Cited by 21 publications

(23 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The feasibility of femtosecond laser ionization and fragmentation of molecules through filamentation for sensing application has been shown in Section by demonstrating fingerprint FINS spectra for air molecules, trace hydrocarbon molecules and aerosols in ambient atmosphere. In this section, we introduce two examples by using the FINS technique for atmospheric humidity measurement , which is an important issue in atmospheric science because it reflects the changes of water concentration in the atmosphere. In addition, filamentation‐assisted water condensation has been recently demonstrated both in a cloud chamber and in the atmosphere , as presented in Fig.…”

Section: Ionization and Fragmentation Of Molecules In Femtosecond Lasmentioning

confidence: 99%

“…Shown in Fig. a is the clear FINS spectrum of water vapor in the spectral range of 306–309 nm when a filament was formed above a conical flask filled with distilled water . OH radical was identified, which was ascribed to the dissociation of water vapor molecules in air.…”

Section: Ionization and Fragmentation Of Molecules In Femtosecond Lasmentioning

confidence: 99%

“…(c) Water temperature dependence on fluorescence intensity of 308.9 nm OH radical; (d) partial pressure of water vapor in air as a function of OH signal at 308.9 nm (with permission of Ref. []. Copyright 2012 Optical Society of America).…”

Section: Ionization and Fragmentation Of Molecules In Femtosecond Lasmentioning

confidence: 99%

See 2 more Smart Citations

Femtosecond laser ionization and fragmentation of molecules for environmental sensing

Cheng

Chin

et al. 2015

Laser & Photonics Reviews

Self Cite

112

View full text Add to dashboard Cite

Recent studies have demonstrated that femtosecond laser pulses have high potential in application to environmental science. Because of the properties of ultrafast, broadband and high power, the propagation of femtosecond laser pulses in air can lead to the generation of a strong field of 1013–1014 W/cm2 with a large distance range from meter to kilometers. The strong laser field induces ionization and fragmentation of molecules in the laser propagation path, resulting in characteristic fingerprint emissions. This paper mainly focuses on recent research advances in environmental sensing by using femtosecond laser pulses through strong‐field‐induced ionization and fragmentation of molecules. The fingerprint emissions of molecules in strong laser fields are discussed based on the understanding of strong‐field–molecule interactions in atmospheric as well as in vacuum environments. This is followed by a comprehensive review of several recently developed optical methods for coherent control of fingerprint emissions of molecules. Lastly, both current challenges and a future perspective of this dynamic field are discussed.

show abstract

Section: Ionization and Fragmentation Of Molecules In Femtosecond Lasmentioning

confidence: 99%

Section: Ionization and Fragmentation Of Molecules In Femtosecond Lasmentioning

confidence: 99%

See 1 more Smart Citation

Femtosecond laser ionization and fragmentation of molecules for environmental sensing

Cheng

Chin

et al. 2015

Laser & Photonics Reviews

Self Cite

112

View full text Add to dashboard Cite

show abstract

“…In addition, evident in the spectra are the emissions by free radicals OH at 307 nm ( A 2 Σ + → X 2 Π ) and NH at 336 nm ( A 3 Π → X 3 Σ − ). These compounds are formed through complex photochemical processes involving water and air molecules . Referencing the amplitudes of the detected spectral lines to that of the OH line, which corresponds to the known ≈1 000 000 ppm water concentration, can be used for the quantitative calibration of the pollutant concentrations.…”

mentioning

confidence: 99%

Robust Remote Sensing of Trace‐Level Heavy‐Metal Contaminants in Water Using Laser Filaments

Zang

et al. 2018

Global Challenges

Self Cite

View full text Add to dashboard Cite

Water is the major natural resource that enables life on our planet. Rapid detection of water pollution that occurs due to both human activity and natural cataclysms is imperative for environmental protection. Analytical chemistry–based techniques are generally not suitable for rapid monitoring because they involve collection of water samples and analysis in a laboratory. Laser‐based approaches such as laser‐induced breakdown spectroscopy (LIBS) may offer a powerful alternative, yet conventional LIBS relies on the use of tightly focused laser beams, requiring a stable air–water interface in a controlled environment. Reported here is a proof‐of‐principle, quantitative, simultaneous measurement of several representative heavy‐metal contaminants in water, at ppm‐level concentrations, using ultraintense femtosecond laser pulses propagating in air in the filamentation regime. This approach is straightforwardly extendable to kilometer‐scale standoff distances, under adverse atmospheric conditions and is insensitive to the movements of the water surface due to the topography and water waves.

show abstract

“…An ultrashort (femtosecond level) duration of laser interaction with samples will also minimize the plasma supercontinuum background, which could improve the signal-to-noise ratio [8] . FIBS has been used for sensing water vapor [9] and environment [10] . When FIBS is used for soil analysis, it has rarely been reported, although there are many publications on soil element analysis using LIBS with nanosecond laser pulses [11] .…”

mentioning

confidence: 99%

Harmonic generation at air–soil interface by femtosecond laser filament

et al. 2017

View full text Add to dashboard Cite

We observe the third-harmonic generation and second-harmonic generation together with element fluorescence from the interaction of a femtosecond laser filament with a rough surface sample (sandy soil) in non-phasematched directions. The harmonics prove to originate from the phase-matched surface harmonics and air filament, then scatter in non-phase-matched directions due to the rough surface. These harmonics occurr when the sample is in the region before and after the laser filament, where the laser intensity is not high enough to excite the element fluorescence. The observed harmonics are related to the element spectroscopy, which will benefit the understanding of the interaction of the laser filament with a solid and be helpful for the application on filament induced breakdown spectroscopy.

show abstract

Water vapor concentration measurement in air using filament-induced fluorescence spectroscopy

Abstract: Water vapor fluorescence in air induced by femtosecond laser filaments was systematically investigated. The fluorescence signal intensity was found to be linearly proportional to the water vapor concentration, which opens up the possibility of absolute humidity measurements, even remotely.

Cited by 21 publications

References 14 publications

Femtosecond laser ionization and fragmentation of molecules for environmental sensing

Femtosecond laser ionization and fragmentation of molecules for environmental sensing

Robust Remote Sensing of Trace‐Level Heavy‐Metal Contaminants in Water Using Laser Filaments

Harmonic generation at air–soil interface by femtosecond laser filament

Contact Info

Product

Resources

About