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Gotti R, Prevedelli M, Kassi S, Marangoni M, Romanini D. Feed-forward coherent link from a comb to a diode laser: Application to widely tunable cavity ring-down spectroscopy. J Chem Phys 2018; 148:054202. [PMID: 29421905 DOI: 10.1063/1.5018611] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We apply a feed-forward frequency control scheme to establish a phase-coherent link from an optical frequency comb to a distributed feedback (DFB) diode laser: This allows us to exploit the full laser tuning range (up to 1 THz) with the linewidth and frequency accuracy of the comb modes. The approach relies on the combination of an RF single-sideband modulator (SSM) and of an electro-optical SSM, providing a correction bandwidth in excess of 10 MHz and a comb-referenced RF-driven agile tuning over several GHz. As a demonstration, we obtain a 0.3 THz cavity ring-down scan of the low-pressure methane absorption spectrum. The spectral resolution is 100 kHz, limited by the self-referenced comb, starting from a DFB diode linewidth of 3 MHz. To illustrate the spectral resolution, we obtain saturation dips for the 2ν3 R(6) methane multiplet at μbar pressure. Repeated measurements of the Lamb-dip positions provide a statistical uncertainty in the kHz range.
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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
| | - 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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2
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Insero G, Clivati C, D'Ambrosio D, Natale PD, Santambrogio G, Schunemann PG, Zondy JJ, Borri S. Difference frequency generation in the mid-infrared with orientation-patterned gallium phosphide crystals. OPTICS LETTERS 2016; 41:5114-5117. [PMID: 27805704 DOI: 10.1364/ol.41.005114] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report on the generation of coherent mid-infrared radiation around 5.85 μm by difference frequency generation (DFG) of a continuous-wave Nd:YAG laser at 1064 nm and a diode laser at 1301 nm in an orientation-patterned gallium phosphide (OP-GaP) crystal. We provide the first characterization of the linear, thermo-optic, and nonlinear properties of OP-GaP in a DFG configuration. Moreover, by comparing the experimental efficiency to Gaussian beam DFG theory, we derive an effective nonlinear coefficient d=17(3) pm/V for first-order quasi-phase-matched OP-GaP. The temperature and signal wavelength tuning curves are in qualitative agreement with theoretical modeling.
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3
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Long DA, Fleisher AJ, Liu Q, Hodges JT. Ultra-sensitive cavity ring-down spectroscopy in the mid-infrared spectral region. OPTICS LETTERS 2016; 41:1612-5. [PMID: 27192300 PMCID: PMC4901391 DOI: 10.1364/ol.41.001612] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We describe an ultra-sensitive cavity ring-down spectrometer which operates in the mid-infrared spectral region near 4.5 μm. With this instrument a noise-equivalent absorption coefficient of 2.6×10-11 cm-1 Hz-1/2 was demonstrated with less than 150 nW of optical power incident on the photodetector. Quantum noise was observed in the individual ring-down decay events, leading to quantum-noise-limited short-time performance. We believe that this spectrometer's combination of high sensitivity and robustness make it well suited for measurements of ultra-trace gas species as well as applications in optics and fundamental physics.
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Affiliation(s)
- D. A. Long
- Material Measurement Laboratory, National Institute of Standards and Technology
| | - A. J. Fleisher
- Material Measurement Laboratory, National Institute of Standards and Technology
| | - Q. Liu
- Material Measurement Laboratory, National Institute of Standards and Technology
| | - J. T. Hodges
- Material Measurement Laboratory, National Institute of Standards and Technology
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Vainio M, Halonen L. Mid-infrared optical parametric oscillators and frequency combs for molecular spectroscopy. Phys Chem Chem Phys 2016; 18:4266-94. [DOI: 10.1039/c5cp07052j] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Review of mid-infrared optical parametric oscillators and frequency combs for high-resolution spectroscopy, including applications in trace gas detection and fundamental research.
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Affiliation(s)
- M. Vainio
- Laboratory of Physical Chemistry
- Department of Chemistry
- University of Helsinki
- Finland
- VTT Technical Research Centre of Finland Ltd
| | - L. Halonen
- Laboratory of Physical Chemistry
- Department of Chemistry
- University of Helsinki
- Finland
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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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Cancio P, Galli I, Bartalini S, Giusfredi G, Mazzotti D, De Natale P. Saturated-Absorption Cavity Ring-Down (SCAR) for High-Sensitivity and High-Resolution Molecular Spectroscopy in the Mid IR. SPRINGER SERIES IN OPTICAL SCIENCES 2014. [DOI: 10.1007/978-3-642-40003-2_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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7
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Galli I, Cappelli F, Cancio P, Giusfredi G, Mazzotti D, Bartalini S, De Natale P. High-coherence mid-infrared frequency comb. OPTICS EXPRESS 2013; 21:28877-85. [PMID: 24514401 DOI: 10.1364/oe.21.028877] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We report on the generation of a frequency comb around 4330 nm with an unprecedented coherence of the single teeth. Generating the comb within a Ti:sapphire laser cavity by a difference-frequency process and using a phase-lock scheme based on direct digital synthesis, we achieve a tooth linewidth of 2.0 kHz in a 1-s timescale (750 Hz in 20 ms). The generated per-tooth power of 1 μW ranks this comb among the best ever realized in the mid-infrared in terms of power spectral density.
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Hansen MG, Ernsting I, Vasilyev SV, Grisard A, Lallier E, Gérard B, Schiller S. Robust, frequency-stable and accurate mid-IR laser spectrometer based on frequency comb metrology of quantum cascade lasers up-converted in orientation-patterned GaAs. OPTICS EXPRESS 2013; 21:27043-27056. [PMID: 24216928 DOI: 10.1364/oe.21.027043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate a robust and simple method for measurement, stabilization and tuning of the frequency of cw mid-infrared (MIR) lasers, in particular of quantum cascade lasers. The proof of principle is performed with a quantum cascade laser at 5.4 µm, which is upconverted to 1.2 µm by sum-frequency generation in orientation-patterned GaAs with the output of a standard high-power cw 1.5 µm fiber laser. Both the 1.2 µm and the 1.5 µm waves are measured by a standard Er:fiber frequency comb. Frequency measurement at the 100 kHz-level, stabilization to sub-10 kHz level, controlled frequency tuning and long-term stability are demonstrated.
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Kuma S, Miyamoto Y, Tsutsumi K, Sasao N, Uetake S. 4.8 μm difference-frequency generation using a waveguide-PPLN crystal and its application to mid-infrared Lamb-dip spectroscopy. OPTICS LETTERS 2013; 38:2825-2828. [PMID: 23903153 DOI: 10.1364/ol.38.002825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Difference-frequency generation of 4.8 μm mid-infrared light was performed using a waveguide periodically poled LiNbO₃ (PPLN) crystal. 871 and 1064 nm external-cavity diode lasers followed by tapered amplifiers were used as pump sources. A conversion efficiency of ~2%/W with the output power of 2 mW was achieved even under considerable absorption of the crystal at this wavelength. Lamb-dip spectroscopy of carbonyl sulfide was demonstrated showing the satisfactory performance of this device for saturation spectroscopy. The observed dip width shows that the laser linewidth is ~2 MHz, which corresponds to those of the pump lasers.
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Affiliation(s)
- Susumu Kuma
- Research Core for Extreme Quantum World, Okayama University, Okayama, Japan. ‑u.ac.jp
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Liao CC, Lien YH, Wu KY, Lin YR, Shy JT. Widely tunable difference frequency generation source for high-precision mid-infrared spectroscopy. OPTICS EXPRESS 2013; 21:9238-9246. [PMID: 23609634 DOI: 10.1364/oe.21.009238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We have developed a widely tunable mid-infrared difference frequency generation (DFG) source by mixing ~ 1 W Ti:sapphire laser and 6 W Nd:YAG laser beams in a 50-mm MgO-doped long periodically poled lithium niobate (MgO:PPLN). The power of the DFG source is > 2 mW over the tuning range of 2.66-4.77 μm and its free-running linewidth is about 100 kHz. Combining various frequency stabilisation schemes for the Nd:YAG laser and the Ti:sapphire laser, the DFG frequency can be precisely controlled. Besides, its frequency can be determined better than 12 kHz by measuring the Ti:sapphire laser frequency using an optical frequency comb. Two high resolution spectroscopic studies on (12)C(16)O(2) molecule are demonstrated using this DFG source. The saturation spectra of R(18) and R(60) transitions of 00(0)1 ← 00(0)0 fundamental band at 4.2 μm and P(20) transition of [10(0)1, 02(0)1](I) ← 00(0)0 band at 2.7 μm have been observed and their absolute transition frequencies are measured with an accuracy better than 30 kHz.
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Affiliation(s)
- Chun-Chieh Liao
- Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
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11
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Galli I, Bartalini S, Cancio Pastor P, Cappelli F, Giusfredi G, Mazzotti D, Akikusa N, Yamanishi M, De Natale P. Absolute frequency measurements of CO2 transitions at 4.3 μm with a comb-referenced quantum cascade laser. Mol Phys 2013. [DOI: 10.1080/00268976.2013.782436] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Iacopo Galli
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Saverio Bartalini
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Pablo Cancio Pastor
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Francesco Cappelli
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Giovanni Giusfredi
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Davide Mazzotti
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
| | - Naota Akikusa
- Development Bureau Laser Device R&D Group, Hamamatsu Photonics KK, , Shizuoka, Japan
| | | | - Paolo De Natale
- Istituto Nazionale di Ottica (INO) – CNR and European Laboratory for Nonlinear Spectroscopy (LENS), , Sesto Fiorentino, FI, Italy
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12
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Cancio P, Bartalini S, De Rosa M, Giusfredi G, Mazzotti D, Maddaloni P, Vitiello M, De Natale P. Atomic and molecular spectroscopy with optical-frequency-comb-referenced IR coherent sources. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20135702003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Asvany O, Krieg J, Schlemmer S. Frequency comb assisted mid-infrared spectroscopy of cold molecular ions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:093110. [PMID: 23020365 DOI: 10.1063/1.4753930] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A mid-infrared spectrometer consisting of a high power optical parametric oscillator, a frequency comb, and a cold ion trap is described and characterized. The idler frequency at 3 μm is measured accurately by analyzing the pump and signal beat frequencies with the comb. This is done via two spectrum analyzers, allowing for a wide and continuous scanning ideal for spectroscopy of cold molecules with unknown spectra. The potential of this approach is demonstrated by measuring a ro-vibrational line of CH(5)(+) in a 22-pole ion trap via action spectroscopy of only several thousand cold ions. The current setup limits the precision of the line center frequency determination to some 100 kHz with ample room for future improvements. Following this approach, ground state combination differences of molecular ions can be predicted in order to identify them in astronomical objects.
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Affiliation(s)
- Oskar Asvany
- I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
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14
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Borri S, Galli I, Cappelli F, Bismuto A, Bartalini S, Cancio P, Giusfredi G, Mazzotti D, Faist J, De Natale P. Direct link of a mid-infrared QCL to a frequency comb by optical injection. OPTICS LETTERS 2012; 37:1011-1013. [PMID: 22446207 DOI: 10.1364/ol.37.001011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A narrow-linewidth comb-linked nonlinear source is used as master radiation to injection lock a room-temperature mid-infrared quantum cascade laser (QCL). This process leads to a direct lock of the QCL to the optical frequency comb, providing the unique features of narrow linewidth, absolute frequency, higher output power, and wide mode-hop-free tunability. The QCL reproduces the injected radiation within more than 94%, with a reduction of the frequency-noise spectral density by 3 to 4 orders of magnitude up to about 100 kHz, and a linewidth narrowing from a few MHz to 20 kHz.
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Affiliation(s)
- S Borri
- Istituto Nazionale di Ottica (INO), Consiglio Nazionale delle Richerche (CNR), Firenze FI, Italy.
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15
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Bressel U, Ernsting I, Schiller S. 5 μm laser source for frequency metrology based on difference frequency generation. OPTICS LETTERS 2012; 37:918-920. [PMID: 22378438 DOI: 10.1364/ol.37.000918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A narrow-linewidth cw 5 μm source based on difference frequency generation of a 1.3 μm quantum dot external cavity diode laser and a cw Nd:YAG laser in periodically poled MgO:LiNbO(3) has been developed and evaluated for spectroscopic applications. The source can be tuned to any frequency in the 5.09-5.13 μm range with an output power up to 0.1 mW, and in the 5.42-5.48 μm range with sub-microwatt output. The output frequency is stabilized and its value determined by measuring the frequency of the two lasers with a remotely located frequency comb. A frequency instability of less than 4 kHz for long integration times and a linewidth smaller than 700 kHz were obtained.
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Affiliation(s)
- Ulf Bressel
- Institut für Experimentalphysik, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany. Ulf.Bressel@uni‐duesseldorf.de
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16
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Galli I, Bartalini S, Borri S, Cancio P, Mazzotti D, De Natale P, Giusfredi G. Molecular gas sensing below parts per trillion: radiocarbon-dioxide optical detection. PHYSICAL REVIEW LETTERS 2011; 107:270802. [PMID: 22243298 DOI: 10.1103/physrevlett.107.270802] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Indexed: 05/31/2023]
Abstract
Radiocarbon ((14)C) concentrations at a 43 parts-per-quadrillion level are measured by using saturated-absorption cavity ringdown spectroscopy by exciting radiocarbon-dioxide ((14)C(16)O(2)) molecules at the 4.5 μm wavelength. The ultimate sensitivity limits of molecular trace gas sensing are pushed down to attobar pressures using a comb-assisted absorption spectroscopy setup. Such a result represents the lowest pressure ever detected for a gas of simple molecules. The unique sensitivity, the wide dynamic range, the compactness, and the relatively low cost of this table-top setup open new perspectives for ^{14}C-tracing applications, such as radiocarbon dating, biomedicine, or environmental and earth sciences. The detection of other very rare molecules can be pursued as well thanks to the wide and continuous mid-IR spectral coverage of the described setup.
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Affiliation(s)
- I Galli
- Istituto Nazionale di Ottica-CNR (INO-CNR) and European Laboratory for Non-Linear Spectroscopy (LENS, Sesto Fiorentino, Italy
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17
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Galli I, Pastor PC, Di Lonardo G, Fusina L, Giusfredi G, Mazzotti D, Tamassia F, De Natale P. The v3band of14C16O2molecule measured by optical-frequency-comb-assisted cavity ring-down spectroscopy. Mol Phys 2011. [DOI: 10.1080/00268976.2011.614284] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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18
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Consolino L, Giusfredi G, De Natale P, Inguscio M, Cancio P. Optical frequency comb assisted laser system for multiplex precision spectroscopy. OPTICS EXPRESS 2011; 19:3155-3162. [PMID: 21369137 DOI: 10.1364/oe.19.003155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A laser system composed of two lasers phase-locked onto an Optical Frequency Comb Synthesizer (OFCS), operating around 1083 nm, was developed. An absolute frequency precision of 6x10(-13) at 1s, limited by the OFCS, was measured with a residual rms phase-noise of 71 mrad and 87 mrad for the two phase-locks, respectively. Multiplex spectroscopy on 1083 nm Helium transitions with this set-up is demonstrated. Generalization of this system to a larger number of OFCS assisted laser sources for wider frequency separations, even in other spectral regions, is discussed.
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Affiliation(s)
- L Consolino
- European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica,Universitá degli Studi di Firenze, Via N. Carrara 1, 50019-Sesto Fiorentino (FI), Italy.
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Galli I, Bartalini S, Borri S, Cancio P, Giusfredi G, Mazzotti D, De Natale P. Ti:sapphire laser intracavity difference-frequency generation of 30 mW cw radiation around 4.5 μm. OPTICS LETTERS 2010; 35:3616-3618. [PMID: 21042368 DOI: 10.1364/ol.35.003616] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A cw mid-IR coherent source based on difference-frequency generation is designed and characterized. For mid-IR generation, a periodically poled MgO:LiNbO(3) crystal is placed inside a compact Ti:sapphire laser cavity. This provides high-power pump radiation for the nonlinear process. Optical injection by an external-cavity diode laser ensures single-frequency operation of the Ti:sapphire laser, while signal radiation is provided by a fiber-amplified Nd:YAG laser. Mid-IR radiation can be generated with 3850-4540 nm tuning range, narrow linewidth, Cs-standard traceability, and TEM(00) spatial mode. 30 mW power is obtained at 4510 nm.
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Affiliation(s)
- I Galli
- Isitituto Nazionale di Ottica (INO)-CNR, Largo Fermi 6, 50125 Firenze FI, Italy
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Di Domenico G, Schilt S, Thomann P. Simple approach to the relation between laser frequency noise and laser line shape. APPLIED OPTICS 2010; 49:4801-4807. [PMID: 20820223 DOI: 10.1364/ao.49.004801] [Citation(s) in RCA: 179] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Frequency fluctuations of lasers cause a broadening of their line shapes. Although the relation between the frequency noise spectrum and the laser line shape has been studied extensively, no simple expression exists to evaluate the laser linewidth for frequency noise spectra that does not follow a power law. We present a simple approach to this relation with an approximate formula for evaluation of the laser linewidth that can be applied to arbitrary noise spectral densities.
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Affiliation(s)
- Gianni Di Domenico
- Laboratoire Temps-Fréquence, Université de Neuchâtel, Avenue de Bellevaux 51, CH-2009 Neuchâtel, Switzerland.
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21
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Giusfredi G, Bartalini S, Borri S, Cancio P, Galli I, Mazzotti D, De Natale P. Saturated-absorption cavity ring-down spectroscopy. PHYSICAL REVIEW LETTERS 2010; 104:110801. [PMID: 20366460 DOI: 10.1103/physrevlett.104.110801] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Indexed: 05/29/2023]
Abstract
We report on a novel approach to cavity ring-down spectroscopy with the sample gas in saturated-absorption regime. This technique allows us to decouple and simultaneously retrieve the empty-cavity background and absorption signal, by means of a theoretical model that we developed and tested. The high sensitivity and frequency precision for spectroscopic applications are exploited to measure, for the first time, the hyperfine structure of an excited vibrational state of 17O12C16O in natural abundance with an accuracy of a few parts in 10{-11}.
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Affiliation(s)
- G Giusfredi
- Istituto Nazionale di Ottica (INO)-CNR, Largo Fermi 6, 50125 Firenze FI, Italy
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