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Zhou X, Zhao G, Li Y, Cheng Z, Jiao K, Zhang B, Zhang Z, Li Y, Yan X, Ma W, Jia S. Optical feedback noise-immune cavity-enhanced optical heterodyne molecular spectrometry for sub-Doppler-broadened detection of C 2H 2. OPTICS LETTERS 2024; 49:202-205. [PMID: 38194528 DOI: 10.1364/ol.507004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 11/28/2023] [Indexed: 01/11/2024]
Abstract
A novel, to the best of our knowledge, noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) has been developed, utilizing optical feedback for laser-to-cavity locking with a common distributed-feedback diode laser. The system incorporates active control of the feedback phase and feedforward control of the laser current, allowing for consecutive laser frequency detuning by scanning a piezoelectric transducer (PZT) attached to the cavity. To enhance the fidelity of the spectroscopic signal, wavelength-modulated (wm) NICE-OHMS is implemented. Benefiting from the optical feedback, a modulation frequency of 15 kHz is achieved, surpassing the frequencies typically used in traditional NICE-OHMS setups. Then, the sub-Doppler-broadened wm-NICE-OHMS signal of acetylene at 1.53 µm is observed. A seven-fold improvement in signal to noise ratio has been demonstrated compared to NICE-OHMS alone and a limit of detection of 6.1 × 10-10cm-1 is achieved.
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Zhao G, Hausmaninger T, Schmidt FM, Ma W, Axner O. High-resolution trace gas detection by sub-Doppler noise-immune cavity-enhanced optical heterodyne molecular spectrometry: application to detection of acetylene in human breath. OPTICS EXPRESS 2019; 27:17940-17953. [PMID: 31252745 DOI: 10.1364/oe.27.017940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 05/28/2019] [Indexed: 06/09/2023]
Abstract
A sensitive high-resolution sub-Doppler detecting spectrometer, based on noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS), for trace gas detection of species whose transitions have severe spectral overlap with abundant concomitant species is presented. It is designed around a NICE-OHMS instrumentation utilizing balanced detection that provides shot-noise limited Doppler-broadened (Db) detection. By synchronous dithering the positions of the two cavity mirrors, the effect of residual etalons between the cavity and other surfaces in the system could be reduced. An Allan deviation of the absorption coefficient of 2.2 × 10-13 cm-1 at 60 s, which, for the targeted transition in C2H2, corresponds to a 3σ detection sensitivity of 130 ppt, is demonstrated. It is shown that despite significant spectral interference from CO2 at the targeted transition, which precludes Db detection of C2H2, acetylene could be detected in exhaled breath of healthy smokers.
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Hua TP, Sun YR, Wang J, Liu AW, Hu SM. Frequency metrology of molecules in the near-infrared by NICE-OHMS. OPTICS EXPRESS 2019; 27:6106-6115. [PMID: 30876204 DOI: 10.1364/oe.27.006106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Noise-immune cavity enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) is extremely sensitive in detecting weak absorption. However, the use of NICE-OHMS for metrology study was also hindered by its sensitivity to influence from various experimental conditions such as the residual amplitude modulation. Here we demonstrate to use NICE-OHMS for precision measurements of Lamb-dip spectra of molecules. After a dedicated investigation of the systematic uncertainties in the NICE-OHMS measurement, the transition frequency of a ro-vibrational line of C2H2 near 789 nm was determined to be 379 639 280 915.3±1.2 kHz (fractional uncertainty 3.2 × 10-12), agreeing well with, but more accurate than, the value determined from previous cavity ring-down spectroscopy measurements. The study indicates the possibility to implement the very sensitive NICE-OHMS method for frequency metrology of molecules, or a molecular clock, in the near-infrared.
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Hua TP, Sun YR, Wang J, Hu CL, Tao LG, Liu AW, Hu SM. Cavity-enhanced saturation spectroscopy of molecules with sub-kHz accuracy. CHINESE J CHEM PHYS 2019. [DOI: 10.1063/1674-0068/cjcp1812272] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Tian-peng Hua
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
| | - Yu Robert Sun
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jin Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Chang-le Hu
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
| | - Lei-gang Tao
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
| | - An-wen Liu
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shui-ming Hu
- Hefei National Laboratory for Physical Sciences at the Microscale, iChem Center, University of Science and Technology of China, Hefei 230026, China
- CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
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5
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Gotti R, Sala T, Prevedelli M, Kassi S, Marangoni M, Romanini D. Feed-forward comb-assisted coherence transfer to a widely tunable DFB diode laser. J Chem Phys 2018; 149:154201. [PMID: 30342456 DOI: 10.1063/1.5046387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The transfer of phase coherence from an ultrastable master laser to a distributed feedback diode laser, using an optical comb as a transfer oscillator, is obtained via a new scheme allowing continuous scanning across the whole tuning range of the slave laser together with absolute frequency determination. This is accomplished without phase lock loops, through a robust high-bandwidth feed-forward control acting directly on the slave laser output radiation. The correction is obtained by means of a dual-parallel Mach-Zehnder interferometer used as an optical single-sideband modulator. Coherence transfer across a master-slave frequency gap of 14 THz yields an ∼10 kHz linewidth providing high injection efficiency of an optical cavity with finesse 250 000. This allows demonstrating a cavity ring-down absorption spectrum of low-pressure ambient air over a 300 GHz spectral window.
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Affiliation(s)
- Riccardo Gotti
- Physics Department of Politecnico di Milano and IFN-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Tommaso Sala
- Physics Department of Politecnico di Milano and IFN-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Marco Prevedelli
- Department of Physics and Astronomy, University of Bologna, Viale Berti-Pichat 6/2, I-40126 Bologna, Italy
| | - Samir Kassi
- Université Grenoble Alpes, CNRS, LIPhy, F-38000 Grenoble, France
| | - Marco Marangoni
- Physics Department of Politecnico di Milano and IFN-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Daniele Romanini
- Université Grenoble Alpes, CNRS, LIPhy, F-38000 Grenoble, France
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Zhao G, Hausmaninger T, Ma W, Axner O. Shot-noise-limited Doppler-broadened noise-immune cavity-enhanced optical heterodyne molecular spectrometry. OPTICS LETTERS 2018; 43:715-718. [PMID: 29444060 DOI: 10.1364/ol.43.000715] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 12/28/2017] [Indexed: 06/08/2023]
Abstract
Shot-noise-limited Doppler-broadened (Db) noise-immune cavity-enhanced optical heterodyne molecular spectrometry (NICE-OHMS) has been realized by implementation of balanced detection. A characterization of the system based on Allan-Werle plots of the absorption coefficient, retrieved by fitting a model function to data, shows that the system has a white noise equivalent absorption per unit length per square root of bandwidth of 2.3×10-13 cm-1 Hz-1/2, solely 44% above the shot noise limit, and a detection sensitivity of 2.2×10-14 cm-1 over 200 s, both being unprecedented for Db NICE-OHMS. The white noise response follows the expected inverse square root dependence on power that is representative of a shot-noise-limited response, which confirms that the system is shot-noise-limited.
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7
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Chen TL, Liu YW. Sub-Doppler resolution near-infrared spectroscopy at 1.28 μm with the noise-immune cavity-enhanced optical heterodyne molecular spectroscopy method. OPTICS LETTERS 2017; 42:2447-2450. [PMID: 28957256 DOI: 10.1364/ol.42.002447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 06/01/2017] [Indexed: 06/07/2023]
Abstract
We report on the sub-Doppler saturation spectroscopy of the nitrous oxide (N2O) overtone transition at 1.28 μm. This measurement is performed by the noise-immune cavity-enhanced optical heterodyne molecular spectroscopy technique based on the quantum-dot (QD) laser. A high intra-cavity power, up to 10 W, reaches the saturation limit of the overtone line using an optical cavity with a high finesse of 1.14(5)×105. At a pressure of several mTorr, the saturation dip is observed with a full width at half-maximum of about 2 MHz and a signal-to-noise ratio of 71. To the best of our knowledge, this is the first saturation spectroscopy of molecular overtone transitions in the 1.3 μm region. The QD laser is then locked to this dispersion signal with a stability of 15 kHz at 1 s integration time. We demonstrate the potential of the N2O as a marker because of its particularly rich spectrum at the vicinity of 1.28-1.30 μm where there are several important forbidden transitions of atomic parity violation measurements and the 1.3 μm O-band of optical communication.
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Cygan A, Wójtewicz S, Kowzan G, Zaborowski M, Wcisło P, Nawrocki J, Krehlik P, Śliwczyński Ł, Lipiński M, Masłowski P, Ciuryło R, Lisak D. Absolute molecular transition frequencies measured by three cavity-enhanced spectroscopy techniques. J Chem Phys 2016; 144:214202. [DOI: 10.1063/1.4952651] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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9
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Hausmaninger T, Silander I, Axner O. Narrowing of the linewidth of an optical parametric oscillator by an acousto-optic modulator for the realization of mid-IR noise-immune cavity-enhanced optical heterodyne molecular spectrometry down to 10⁻¹⁰ cm⁻¹ Hz⁻¹/². OPTICS EXPRESS 2015; 23:33641-33655. [PMID: 26832028 DOI: 10.1364/oe.23.033641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The linewidth of a singly resonant optical parametric oscillator (OPO) has been narrowed with respect to an external cavity by the use of an acousto-optic modulator (AOM). This made possible an improvement of the sensitivity of a previously realized OPO-based noise-immune cavity-enhanced optical heterodyne molecular spectrometry instrument for the 3.2 - 3.9 µm mid-infrared region by one order of magnitude. The resulting system shows a detection sensitivity for methane of 2.4 × 10(-10) cm(-1) Hz(-1∕2) and 1.3 × 10(-10) cm(-1) at 20 s, which allows for detection of both the environmentally important (13)CH(4) and CH(3)D isotopologues in atmospheric samples.
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Centeno R, Mandon J, Cristescu SM, Axner O, Harren FJM. External cavity diode laser-based detection of trace gases with NICE-OHMS using current modulation. OPTICS EXPRESS 2015; 23:6277-6282. [PMID: 25836848 DOI: 10.1364/oe.23.006277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We combine an external cavity diode laser with noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) using current modulation. With a finesse of 1600, we demonstrate noise equivalent absorption sensitivities of 4.1 x 10(-10) cm(-1) Hz(-1/2), resulting in sub-ppbv detection limits for Doppler-broadened transitions of CH(4) at 6132.3 cm(-1), C(2)H(2) at 6578.5 cm(-1) and HCN at 6541.7 cm(-1). The system is used for hydrogen cyanide detection from sweet almonds.
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Dinesan H, Fasci E, D'Addio A, Castrillo A, Gianfrani L. Characterization of the frequency stability of an optical frequency standard at 1.39 µm based upon noise-immune cavity-enhanced optical heterodyne molecular spectroscopy. OPTICS EXPRESS 2015; 23:1757-1766. [PMID: 25835931 DOI: 10.1364/oe.23.001757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Frequency fluctuations of an optical frequency standard at 1.39 µm have been measured by means of a highly-sensitive optical frequency discriminator based on the fringe-side transmission of a high finesse optical resonator. Built on a Zerodur spacer, the optical resonator exhibits a finesse of 5500 and a cavity-mode width of about 120 kHz. The optical frequency standard consists of an extended-cavity diode laser that is tightly stabilized against the center of a sub-Doppler H(2) (18)O line, this latter being detected by means of noise-immune cavity-enhanced optical heterodyne molecular spectroscopy. The emission linewidth has been carefully determined from the frequency-noise power spectral density by using a rather simple approximation, known as β-line approach, as well as the exact method based on the autocorrelation function of the laser light field. It turns out that the linewidth of the optical frequency standard amounts to about 7 kHz (full width at half maximum) for an observation time of 1 ms. Compared to the free-running laser, the measured width corresponds to a line narrowing by a factor of ~220.
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Dinesan H, Fasci E, Castrillo A, Gianfrani L. Absolute frequency stabilization of an extended-cavity diode laser by means of noise-immune cavity-enhanced optical heterodyne molecular spectroscopy. OPTICS LETTERS 2014; 39:2198-2201. [PMID: 24686710 DOI: 10.1364/ol.39.002198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We implemented an optical frequency standard based on noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) at 1.39 μm. The emission frequency of an extended-cavity diode laser was actively stabilized against the center of the 4(4,1)→4(4,0) transition of the H(2)(18)O ν1+ν3 band, under optical saturation conditions. The nonlinear regime of laser-gas interaction was reached by using an optical cavity with a finesse of about 8700. By filling it with an 18O-enriched water sample at a pressure of a few Pa, the Lamb dip could be observed with a full width at half-maximum of about 2 MHz. Absolute frequency stabilization was obtained by locking the cavity resonance to the center of the sub-Doppler signal, which was provided by the NICE-OHMS technique under the dispersion regime of operation. An Allan deviation analysis demonstrated a relative frequency stability of ∼5×10(-13) for an integration time of 1 s. For longer integration times, the flicker frequency noise floor set the stability at the level of 4×10(-14).
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Ehlers P, Silander I, Wang J, Foltynowicz A, Axner O. Fiber-laser-based noise-immune cavity-enhanced optical heterodyne molecular spectrometry incorporating an optical circulator. OPTICS LETTERS 2014; 39:279-282. [PMID: 24562126 DOI: 10.1364/ol.39.000279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To reduce the complexity of fiber-laser-based noise-immune cavity-enhanced optical heterodyne molecular spectrometry, a system incorporating a fiber-coupled optical circulator to deflect the cavity-reflected light for laser stabilization has been realized. Detection near the shot-noise limit has been demonstrated for both Doppler-broadened and sub-Doppler signals, yielding a lowest detectable absorption and optical phase shift of 2.2×10(-12) cm(-1) and 4.0×10(-12) cm(-1), respectively, both for a 10 s integration time, where the former corresponds to a detection limit of C2H2 of 5 ppt.
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14
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Hodges JN, Perry AJ, Jenkins PA, Siller BM, McCall BJ. High-precision and high-accuracy rovibrational spectroscopy of molecular ions. J Chem Phys 2013; 139:164201. [DOI: 10.1063/1.4825251] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Crabtree KN, Hodges JN, Siller BM, Perry AJ, Kelly JE, Jenkins PA, McCall BJ. Sub-Doppler mid-infrared spectroscopy of molecular ions. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.09.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Nikodem M, Wysocki G. Molecular dispersion spectroscopy--new capabilities in laser chemical sensing. Ann N Y Acad Sci 2012; 1260:101-11. [PMID: 22809459 DOI: 10.1111/j.1749-6632.2012.06660.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Laser spectroscopic techniques suitable for molecular dispersion sensing enable new applications and strategies in chemical detection. This paper discusses the current state of the art and provides an overview of recently developed chirped laser dispersion spectroscopy (CLaDS)-based techniques. CLaDS and its derivatives allow for quantitative spectroscopy of trace gases and enable new capabilities, such as extended dynamic range of concentration measurements, high immunity to photodetected intensity fluctuations, or capability of direct processing of spectroscopic signals in optical domain. Several experimental configurations based on quantum cascade lasers and examples of molecular spectroscopic data are presented to demonstrate capabilities of molecular dispersion spectroscopy in the mid-infrared spectral region.
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Affiliation(s)
- Michal Nikodem
- Electrical Engineering Department, Princeton University, Princeton, New Jersey, USA
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17
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Wysocki G, Weidmann D. Molecular dispersion spectroscopy for chemical sensing using chirped mid-infrared quantum cascade laser. OPTICS EXPRESS 2010; 18:26123-26140. [PMID: 21164961 DOI: 10.1364/oe.18.026123] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A spectroscopic method of molecular detection based on dispersion measurements using a frequency-chirped laser source is presented. An infrared quantum cascade laser emitting around 1912 cm(-1) is used as a tunable spectroscopic source to measure dispersion that occurs in the vicinity of molecular ro-vibrational transitions. The sample under study is a mixture of nitric oxide in dry nitrogen. Two experimental configurations based on a coherent detection scheme are investigated and discussed. The theoretical models, which describe the observed spectral signals, are developed and verified experimentally. The method is particularly relevant to optical sensing based on mid-infrared quantum cascade lasers as the high chirp rates available with those sources can significantly enhance the magnitude of the measured dispersion signals. The method relies on heterodyne beatnote frequency measurements and shows high immunity to variations in the optical power received by the photodetector.
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Affiliation(s)
- Gerard Wysocki
- Electrical Engineering Department, Princeton University, Princeton, New Jersey 08544, USA.
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18
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Foltynowicz A, Wang J, Ehlers P, Axner O. Distributed-feedback-laser-based NICE-OHMS in the pressure-broadened regime. OPTICS EXPRESS 2010; 18:18580-18591. [PMID: 20940750 DOI: 10.1364/oe.18.018580] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A compact noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) system based on a narrow linewidth distributed-feedback laser and fiber-coupled acousto-optic and electro-optic modulators has been developed. Measurements of absorption and dispersion signals have been performed at pressures up to 1/3 atmosphere on weak acetylene transitions at 1551 nm. Multiline fitting routines were implemented to obtain transition parameters, i.e., center frequencies, linestrengths, and pressure broadening coefficients. The signal strength was shown to be linear with pressure and concentration, and independent of detection phase. The minimum detectable on-resonance absorption with a cavity with a finesse of 460 was 2 × 10(-10) cm(-1) for 1 minute of integration time.
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Bell CL, Hancock G, Peverall R, Ritchie GAD, van Helden JH, van Leeuwen NJ. Characterization of an external cavity diode laser based ring cavity NICE-OHMS system. OPTICS EXPRESS 2009; 17:9834-9839. [PMID: 19506633 DOI: 10.1364/oe.17.009834] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The performance of an external cavity diode laser based noise immune cavity enhanced optical heterodyne molecular spectrometer is presented. To reduce the noise on the signal a ring cavity and a circuit to remove residual amplitude modulation on the pre-cavity laser radiation was implemented. We demonstrate a sensitivity of 4 x 10(-11) cm(-1) Hz(-1/2) using a cavity with a finesse of 2600 on a Doppler-broadened transition of CH(4) at 6610.063 cm(-1).
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Affiliation(s)
- C L Bell
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, UK
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