Architecture for microcomb-based GHz-mid-infrared dual-comb spectroscopy

AbstractDual-comb spectroscopy (DCS) offers high sensitivity and wide spectral coverage without the need for bulky spectrometers or mechanical moving parts. And DCS in the mid-infrared (mid-IR) is of keen interest because of inherently strong molecular spectroscopic signatures in these bands. We report GHz-resolution mid-IR DCS of methane and ethane that is derived from counter-propagating (CP) soliton microcombs in combination with interleaved difference frequency generation. Because all four combs required to generate the two mid-IR combs rely upon stability derived from a single high-Q microcavity, the system architecture is both simplified and does not require external frequency locking. Methane and ethane spectra are measured over intervals as short as 0.5 ms, a time scale that can be further reduced using a different CP soliton arrangement. Also, tuning of spectral resolution on demand is demonstrated. Although at an early phase of development, the results are a step towards mid-IR gas sensors with chip-based architectures for chemical threat detection, breath analysis, combustion studies, and outdoor observation of trace gases.

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Kagome Hollow Core Fiber-Based Mid-Infrared Dispersion Spectroscopy of Methane at Sub-ppm Levels

Sensors ◽

10.3390/s19153352 ◽

2019 ◽

Vol 19 (15) ◽

pp. 3352 ◽

Cited By ~ 9

Author(s):

Karol Krzempek ◽

Krzysztof Abramski ◽

Michal Nikodem

Keyword(s):

Gas Sensors ◽

Gas Sensing ◽

Difference Frequency Generation ◽

Hollow Core ◽

Large Core ◽

Core Diameter ◽

Mid Infrared ◽

Core Fiber ◽

Crystal Fibers ◽

Long Fibers

In this paper, we demonstrate the laser-based gas sensing of methane near 3.3 µm inside hollow-core photonic crystal fibers. We exploit a novel anti-resonant Kagome-type hollow-core fiber with a large core diameter (more than 100 µm) which results in gas filling times of less than 10 s for 1.3-m-long fibers. Using a difference frequency generation source and chirped laser dispersion spectroscopy technique, methane sensing with sub-parts-per-million by volume detection limit is performed. The detection of ambient methane is also demonstrated. The presented results indicate the feasibility of using a hollow-core fiber for increasing the path-length and improving the sensitivity of the mid-infrared gas sensors.

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Towards lab-on-chip ultrasensitive ethanol detection using photonic crystal waveguide operating in the mid infrared

Nanophotonics ◽

10.1515/nanoph-2020-0576 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Ali Rostamian ◽

Ehsan Madadi-Kandjani ◽

Hamed Dalir ◽

Volker J. Sorger ◽

Ray T. Chen

Keyword(s):

Photonic Crystal ◽

Slow Light ◽

High Sensitivity ◽

Guided Wave ◽

Silicon On Insulator ◽

Group Index ◽

Photonic Crystal Waveguide ◽

Mid Infrared ◽

Lab On Chip ◽

On Chip

Abstract Thanks to the unique molecular fingerprints in the mid-infrared spectral region, absorption spectroscopy in this regime has attracted widespread attention in recent years. Contrary to commercially available infrared spectrometers, which are limited by being bulky and cost-intensive, laboratory-on-chip infrared spectrometers can offer sensor advancements including raw sensing performance in addition to use such as enhanced portability. Several platforms have been proposed in the past for on-chip ethanol detection. However, selective sensing with high sensitivity at room temperature has remained a challenge. Here, we experimentally demonstrate an on-chip ethyl alcohol sensor based on a holey photonic crystal waveguide on silicon on insulator-based photonics sensing platform offering an enhanced photoabsorption thus improving sensitivity. This is achieved by designing and engineering an optical slow-light mode with a high group-index of n g = 73 and a strong localization of modal power in analyte, enabled by the photonic crystal waveguide structure. This approach includes a codesign paradigm that uniquely features an increased effective path length traversed by the guided wave through the to-be-sensed gas analyte. This PIC-based lab-on-chip sensor is exemplary, spectrally designed to operate at the center wavelength of 3.4 μm to match the peak absorbance for ethanol. However, the slow-light enhancement concept is universal offering to cover a wide design-window and spectral ranges towards sensing a plurality of gas species. Using the holey photonic crystal waveguide, we demonstrate the capability of achieving parts per billion levels of gas detection precision. High sensitivity combined with tailorable spectral range along with a compact form-factor enables a new class of portable photonic sensor platforms when combined with integrated with quantum cascade laser and detectors.

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Zinc‐oxide thin‐film ammonia gas sensors with high sensitivity and excellent selectivity

Journal of Applied Physics ◽

10.1063/1.337435 ◽

1986 ◽

Vol 60 (2) ◽

pp. 482-484 ◽

Cited By ~ 250

Author(s):

Hidehito Nanto ◽

Tadatsugu Minami ◽

Shinzo Takata

Keyword(s):

Thin Film ◽

Zinc Oxide ◽

Gas Sensors ◽

High Sensitivity ◽

Oxide Thin Film ◽

Zinc Oxide Thin Film ◽

Ammonia Gas ◽

Ammonia Gas Sensors ◽

Excellent Selectivity

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Collision Induced Microwave Absorption in N2, CH4, and N2–Ar, N2–CH4 Mixtures at 1.1 and 2.3 cm−1

Canadian Journal of Physics ◽

10.1139/p74-112 ◽

1974 ◽

Vol 52 (9) ◽

pp. 821-829 ◽

Cited By ~ 8

Author(s):

I. R. Dagg ◽

G. E. Reesor ◽

J. L. Urbaniak

Keyword(s):

Microwave Absorption ◽

Quadrupole Moment ◽

Linear Dependence ◽

Relaxation Times ◽

High Sensitivity ◽

Higher Order ◽

Induced Absorption ◽

High Q ◽

Order Dependence

Collision induced microwave absorption is reported in pure N2, N2–Ar, N2–CH4, mixtures, and in pure CH4 in the 35 and 70 GHz regions (1.1 and 2.3 cm−1) at a temperature of 22 °C. The measurements are accomplished using overmoded high Q cavities capable of pressurization of up to 5000 p.s.i.g. The apparatus and method are described. With the high sensitivity attained, the results in pure N2 from 30 → 250 amagat reveal terms in the square and cube of the density from which the relaxation times are calculated. The linear dependence on frequency of the collision induced absorption up to 2.3 cm−1 is established. Higher order dependence on the density is observed in the N2–Ar and N2–CH4 mixtures. Various estimates of the quadrupole moment of N2 are given, making use of earlier results in other frequency regions.

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Mid-infrared spectroscopic signatures of dibenzopyrene cations – The effect of symmetry on PAH IR spectroscopy

Journal of Molecular Spectroscopy ◽

10.1016/j.jms.2021.111458 ◽

2021 ◽

Vol 378 ◽

pp. 111458

Author(s):

Jordy Bouwman ◽

Harold Linnartz ◽

Alexander G.G.M. Tielens

Keyword(s):

Ir Spectroscopy ◽

Mid Infrared ◽

Infrared Spectroscopic ◽

Spectroscopic Signatures

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Mid-infrared photoacoustic gas monitoring driven by a gas-filled hollow-core fiber laser

Scientific Reports ◽

10.1038/s41598-021-83041-2 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Yazhou Wang ◽

Yuyang Feng ◽

Abubakar I. Adamu ◽

Manoj K. Dasa ◽

J. E. Antonio-Lopez ◽

...

Keyword(s):

Fiber Laser ◽

Signal To Noise Ratio ◽

High Sensitivity ◽

Laser Source ◽

High Signal ◽

Mid Infrared ◽

Raman Fiber Laser ◽

Custom Made ◽

Core Fiber ◽

Detection Technologies

AbstractDevelopment of novel mid-infrared (MIR) lasers could ultimately boost emerging detection technologies towards innovative spectroscopic and imaging solutions. Photoacoustic (PA) modality has been heralded for years as one of the most powerful detection tools enabling high signal-to-noise ratio analysis. Here, we demonstrate a novel, compact and sensitive MIR-PA system for carbon dioxide (CO2) monitoring at its strongest absorption band by combining a gas-filled fiber laser and PA technology. Specifically, the PA signals were excited by a custom-made hydrogen (H2) based MIR Raman fiber laser source with a pulse energy of ⁓ 18 μJ, quantum efficiency of ⁓ 80% and peak power of ⁓ 3.9 kW. A CO2 detection limit of 605 ppbv was attained from the Allan deviation. This work constitutes an alternative method for advanced high-sensitivity gas detection.

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Spectroscopic Imaging with an Ultra-Broadband (1–4 THz) Compact Terahertz Difference-Frequency Generation Source

Electronics ◽

10.3390/electronics10030336 ◽

2021 ◽

Vol 10 (3) ◽

pp. 336

Author(s):

Atsushi Nakanishi ◽

Shohei Hayashi ◽

Hiroshi Satozono ◽

Kazuue Fujita

Keyword(s):

Imaging Technique ◽

Spectroscopic Imaging ◽

Difference Frequency Generation ◽

Difference Frequency ◽

Quality Monitoring ◽

Terahertz Emission ◽

Mid Infrared ◽

Quantum Cascade ◽

Frequency Generation ◽

Multi Mode

We demonstrate spectroscopic imaging using a compact ultra-broadband terahertz semiconductor source with a high-power, mid-infrared quantum cascade laser. The electrically pumped monolithic source is based on intra-cavity difference-frequency generation and can be designed to achieve an ultra-broadband multi-mode terahertz emission spectrum extending from 1–4 THz without any external optical setup. Spectroscopic imaging was performed with three frequency bands, 2.0 THz, 2.5 THz and 3.0 THz, and as a result, this imaging technique clearly identified three different tablet components (polyethylene, D-histidine and DL-histidine). This method may be highly suitable for quality monitoring of pharmaceutical materials.

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Direct Production of a Novel Iron-Based Nanocomposite from the Laser Pyrolysis ofFe(CO)5/MMAMixtures: Structural and Sensing Properties

Journal of Nanomaterials ◽

10.1155/2010/324532 ◽

2010 ◽

Vol 2010 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

R. Alexandrescu ◽

I. Morjan ◽

A. Tomescu ◽

C. E. Simion ◽

M. Scarisoreanu ◽

...

Keyword(s):

Iron Oxide ◽

Gas Sensors ◽

High Sensitivity ◽

X Ray Diffraction ◽

Direct Production ◽

X Ray ◽

Metallic Particles ◽

Ir Laser ◽

Iron Iron ◽

Optimum Working

Iron/iron oxide-based nanocomposites were prepared by IR laser sensitized pyrolysis ofFe(CO)5and methyl methacrylate (MMA) mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core-shell structures were obtained. X-ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized) polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence ofNO2, CO, andCO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towardsNO2detection andNO2selectivity relatively to CO andCO2. An optimum working temperature of200°Cwas found.

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