Precise multispecies agricultural gas flux determined using broadband open-path dual-comb spectroscopy

Herman, Daniel I.; Weerasekara, Chinthaka; Hutcherson, Lindsay C.; Giorgetta, Fabrizio R.; Cossel, Kevin C.; Waxman, E.; Colacion, Gabriel M.; Newbury, Nathan R.; Welch, Stephen M.; DePaola, B. D.; Coddington, Ian; Santos, Eduardo A.; Washburn, Brian R.

doi:10.1126/sciadv.abe9765

Cited by 51 publications

(20 citation statements)

References 68 publications

(107 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Coherent light sources in the MIR frequency range (3 µm to 25 µm) are critical for molecular spectroscopy as applied to fundamental materials science and chemistry [55,56], environmental monitoring [57,58], the determination of protein structure [59], combustion analysis [60,61] and medical diagnostics such as breath analysis [62]. With high peak power and a broad spectrum, the output pulse is suitable to produce MIR pulse through IP-DFG, which we explore with both OP-GaAs and CSP.…”

Section: Mir Generation and Characterizationmentioning

confidence: 99%

Single-cycle all-fiber frequency comb

Xing,

Lesko,

Umeki

et al. 2021

Preprint

View full text Add to dashboard Cite

Single-cycle pulses with deterministic carrier-envelope phase enable the study and control of light-matter interactions at the sub-cycle timescale, as well as the efficient generation of low-noise multi-octave frequency combs. However, current single-cycle light sources are difficult to implement and operate, hindering their application and accessibility in a wider range of research. In this paper, we present a single-cycle 100 MHz frequency comb in a compact, turn-key, and reliable all-silica-fiber format. This is achieved by amplifying 2 µm seed pulses in heavily-doped Tm:fiber, followed by cascaded self-compression to yield 6.8 fs pulses with 215 kW peak power and 374 mW average power. The corresponding spectrum covers more than two octaves, from below 700 nm up to 3500 nm. Driven by this single-cycle pump, supercontinuum with 180 mW of integrated power and a smooth spectral amplitude between 2100 and 2700 nm is generated directly in silica fibers. To broaden applications,few-cycle pulses extending from 6 µm to beyond 22 µm with long-term stable carrier-envelope phase are created using intra-pulse difference frequency, and electro-optic sampling yields comb-tooth-resolved spectra. Our work demonstrates the first all-fiber configuration that generates single-cycle pulses, and provides a practical source to study nonlinear optics on the same timescale.

show abstract

Section: Mir Generation and Characterizationmentioning

confidence: 99%

Single-cycle all-fiber frequency comb

Xing,

Lesko,

Umeki

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Since molecular absorptions are strongest and highly speci c in the mid-infrared (MIR) range, lasers in this region can potentially provide a higher sensitivity. A variety of broadband MIR laser sources have been realized, such as frequency combs (FC) 7,22,23,24,25 , super-continuum sources (SC) 21 , quantum cascade lasers (QCLs) 1,19 that were combined with high sensitivity optical methods to further improve the detection limit and robustness of spectroscopic systems. However, in addition to a high measurement sensitivity, achieving a high speci city often poses an even greater challenge due to overlapping of the absorption spectra of different components 21 .…”

Section: Introductionmentioning

confidence: 99%

Neural network multi-component gas mixture analysis with broadband dual-frequency comb absorption spectroscopy

Tian

Xia

Kolomenskii

et al. 2022

Preprint

View full text Add to dashboard Cite

The cross interference of gas species in absorption spectroscopy is one of the most challenging obstacles for the analysis of multi-component gas mixtures with overlapping absorption features (blended spectra). We propose a multi-component gas mixture sensor combining a broadband absorption spectrum acquisition with a spectrum analysis algorithm. The sensor features a mid-infrared dual-frequency comb laser source enabling sensitive measurements in a broad spectral interval combined with a deep learning algorithm for spectral analysis to accurately identify the species and retrieve the concentrations of the gas components in the mixture. The sensor is tested with gas mixtures of three common gas species, namely methane, acetone and water vapor. The architecture tuning and model training are achieved by a physics-informed augmented dataset. The proposed spectral analysis model is evaluated firstly by comparison with two other state-of-the-art neural network algorithms (2L-ARNN and 1D-CNN). The performance of the complete sensor is then assessed by real-time measurements in realistic detection scenarios. In addition, we systematically analyzed and presented explicit visualizations explaining the inner working mechanism of the considered algorithms. The high performance of the proposed sensor suggests that it is feasible to realize schemes for more general gas mixture analysis by integrating broadband optical sensing and deep learning models.

show abstract

“…The analysis was based on a cavity ring-down spectrometer (Picarro, G1301 and G2401) with a precision better than 0.7 ppb. Moreover, agricultural CH 4 concentrations measured in a field of 0.42 hectares had a variation of 0.1 ppm during 24 h, using broadband openpath dual-comb spectroscopy that provided methane measurements with a precision of 25 ppb [18]. We can deduce from these publications that GHG emissions from small-scale areas can be reliably estimated using atmospheric measurements from instruments with lower sensitivity and higher detection limits than those measuring concentrations globally, such as satellite observatories.…”

Section: Introductionmentioning

confidence: 99%

Autonomous Differential Absorption Laser Device for Remote Sensing of Atmospheric Greenhouse Gases

et al. 2022

View full text Add to dashboard Cite

A ground-based, integrated path, differential absorption (IPDA) light detection device capable of measuring multiple greenhouse gas (GHG) species in the atmosphere is presented. The device was developed to monitor greenhouse gas concentrations in small-scale areas with high emission activities. It is equipped with two low optical power tunable diode lasers in the near-infrared spectral range for the atmospheric detection of carbon dioxide, methane, and water vapors (CO2, CH4 and H2O). The device was tested with measurements of background concentrations of CO2 and CH4 in the atmosphere (Crete, Greece). Accuracies in the measurement retrievals of CO2 and CH4 were estimated at 5 ppm (1.2%) and 50 ppb (2.6%), respectively. A method that exploits the intensity of the recorded H2O absorption line in combination with weather measurements (water vapor pressure, temperature, and atmospheric pressure) to calculate the GHG concentrations is proposed. The method eliminates the requirement for measuring the range of the laser beam propagation. Accuracy in the measurement of CH4 using the H2O absorption line is estimated at 90 ppb (4.8%). The values calculated by the proposed method are in agreement with those obtained from the differential absorption LiDAR equation (DIAL).

show abstract

Precise multispecies agricultural gas flux determined using broadband open-path dual-comb spectroscopy

Cited by 51 publications

References 68 publications

Single-cycle all-fiber frequency comb

Single-cycle all-fiber frequency comb

Neural network multi-component gas mixture analysis with broadband dual-frequency comb absorption spectroscopy

Autonomous Differential Absorption Laser Device for Remote Sensing of Atmospheric Greenhouse Gases

Contact Info

Product

Resources

About