Dominik Charczun
@princeton.edu
Frick Chemistry Laboratory
Princeton University
RESEARCH, TEACHING, or OTHER INTERESTS
Spectroscopy, Atomic and Molecular Physics, and Optics
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Romain Dubroeucq, Dominik Charczun, Piotr Masłowski, and Lucile Rutkowski
IEEE
Multiplexed cavity ring-down spectroscopy (CRDS) is challenging to achieve as it requires a detection scheme able to retrieve many undistorted exponential decays simultaneously [1]. We recently demonstrated Fourier transform CRDS (FT-CRDS) based on an optical frequency comb source and a time-resolved Fourier transform spectrometer (FTS) [2]. In this proof-of-concept experiment, the frequency comb was locked to a CRDS cavity using the Pound-Drever-Hall (PDH) technique, to ensure a quasi-continuous comb light transmission through the cavity. The decays were synchronized with the movement of the fast-scanning FTS, allowing to retrieve a 3D spectrum containing the untangled decays at each spectral element. The cavity was characterized by a moderate finesse of 2,000, far below standard reflectivity used for CRDS, and the comb mode absolute frequencies were not stabilized. Here, we revise the locking scheme, as depicted in Fig. 1(a): the offset frequency of the Erbium comb is stabilized to a reference radiofrequency while the repetition rate is phase-locked to a continuous wave laser emitting at 1550 nm, which in turn is locked to a cavity mode using the Pound-Drever-Hall technique. Absolute frequency stability is ensured by actively stabilizing the repetition rate to a tunable reference acting on the piezo-actuator glued to one of the cavity mirrors. The cavity transmission is sent to the FTS where it propagates parallel to a frequency-stabilized HeNe laser whose interferogram is used for optical path difference (OPD) calibration. This reference is also used to trigger the acousto-optic modulator switching off the comb light, allowing retrieval of cavity decays with a controlled OPD step. Fast Fourier transformation of the comb interferograms obtained at different delays after the triggers yields the ring-down events in spectral domain. Finally, these exponential decays are fitted individually to retrieve the CRDS spectrum, which is directly proportional to the absorption coefficient of the analyte, without requiring knowledge of the cavity length or finesse. In addition, as the comb frequencies are stable in time, averaging of successive measurements is now possible.
Daniel Lisak, Dominik Charczun, Akiko Nishiyama, Thibault Voumard, Thibault Wildi, Grzegorz Kowzan, Victor Brasch, Tobias Herr, Adam J. Fleisher, Joseph T. Hodges,et al.
Springer Science and Business Media LLC
AbstractCavity ring-down spectroscopy is a ubiquitous optical method used to study light-matter interactions with high resolution, sensitivity and accuracy. However, it has never been performed with the multiplexing advantages of direct frequency comb spectroscopy without significantly compromising spectral resolution. We present dual-comb cavity ring-down spectroscopy (DC-CRDS) based on the parallel heterodyne detection of ring-down signals with a local oscillator comb to yield absorption and dispersion spectra. These spectra are obtained from widths and positions of cavity modes. We present two approaches which leverage the dynamic cavity response to coherently or randomly driven changes in the amplitude or frequency of the probe field. Both techniques yield accurate spectra of methane—an important greenhouse gas and breath biomarker. When combined with broadband frequency combs, the high sensitivity, spectral resolution and accuracy of our DC-CRDS technique shows promise for applications like studies of the structure and dynamics of large molecules, multispecies trace gas detection and isotopic composition.
Akiko Nishiyama, Grzegorz Kowzan, Dominik Charczun, and Piotr Masłowski
IEEE
We developed a mid-infrared optical frequency comb-based Fourier-transform spectroscopy system and applied for line-shape study of fundamental vibrational band of CO. The technique allows to determine line-shape parameters precisely in wide range of midinfrared region.
D. Charczun, D. Lisak, A. Nishiyama, T. Voumard, T. Wildi, G. Kowzan, V. Brasch, T. Herr, A. J. Fleisher, J. T. Hodges,et al.
IEEE
The advantages of dual-comb spectroscopy with the sensitivity of cavity-enhanced techniques has been combined in a new broadband approach. The experimental demonstration is completed by a comprehensive theoretical framework, underlining the potential of the techniques.
D. Charczun, D. Lisak, A. Nishiyama, T. Voumard, T. Wildi, G. Kowzan, V. Brasch, T. Herr, A. J. Fleisher, J. T. Hodges,et al.
Optica Publishing Group
The advantages of dual-comb spectroscopy with the sensitivity of cavity-enhanced techniques has been combined in a new broadband approach. The experimental demonstration is completed by a comprehensive theoretical framework, underlining the potential of the techniques.
Akiko Nishiyama, Grzegorz Kowzan, Dominik Charczun, and Piotr Masłowski
Optica Publishing Group
We developed a mid-infrared optical frequency comb-based Fourier-transform spectroscopy system and applied for line-shape study of fundamental vibrational band of CO. The technique allows to determine line-shape parameters precisely in wide range of mid-infrared region.
D. Charczun, A. Nishiyama, G. Kowzan, A. Cygan, T. Voumard, T. Wildi, T. Herr, V. Brasch, D. Lisak, and P. Masłowski
Elsevier BV
Katarzyna Bielska, Agata Cygan, Magdalena Konefał, Grzegorz Kowzan, Mikołaj Zaborowski, Dominik Charczun, Szymon Wójtewicz, Piotr Wcisło, Piotr Masłowski, Roman Ciuryło,et al.
Optica Publishing Group
Frequency-based cavity mode-dispersion spectroscopy (CMDS), previously applied for Doppler-limited molecular spectroscopy, is now employed for the first time for saturation spectroscopy. Comparison with two intensity-based, cavity-enhanced absorption spectroscopy techniques, i.e. cavity mode-width spectroscopy (CMWS) and the well-established cavity ring-down spectroscopy (CRDS), shows the predominance of the CMDS. The method enables measurements in broader pressure range and shows high immunity of the Lamb dip position to the incomplete model of saturated cavity mode shape. Frequencies of transitions from the second overtone of CO are determined with standard uncertainty below 500 Hz which corresponds to relative uncertainty below 3 × 10−12. The pressure shift of the Lamb dips, which has not been detected for these transitions in available literature data, is observed.
D. Charczun, A. Nishiyama, G. Kowzan, A. Cygan, T. Voumard, T. Wildi, T. Herr, E. Obrzud, V. Brasch, D. Lisak,et al.
IEEE
In the last decade dual comb spectroscopy (DCS) has matured into a powerful tool for applications in various fields [1] . However, combining DCS with an optical enhancement cavity is so far relatively unexplored, with only a few demonstrations until now [2] – [5] , which required the measurement of reference spectrum and the correction of the measured molecular spectrum for the comb-cavity frequency mismatch [6] . As a way to circumvent those limitations, we present dual-comb measurements of widths and positions of enhancement cavity modes to retrieve molecular absorption and dispersion spectrum and we demonstrate it on methane sample (20% mixture in nitrogen). This method has been previously demonstrated with continuous wave (CW) lasers [7] and broadband comb-based mechanical Fourier-transform (FT) [8] , and dispersive [9] spectrometers.
Akiko Nishiyama, Grzegorz Kowzan, Dominik Charczun, Ryszard S. Trawiński, and Piotr Masłowski
AIP Publishing
Direct-comb spectroscopy techniques uses optical frequency combs (OFCs) as spectroscopic light source. They deliver high sensitivity, high frequency resolution and precision in a broad spectral range. Due to these features, the field has burgeoned in recent years. In this work we constructed an OFC-based cavity-enhanced Fourier-transform spectrometer in the near-infrared region and used it for a line-shape study of rovibrational transitions of CO perturbed by Ar. The highly sensitive measurements spanned the wavenumber range from 6270 cm−1 to 6410 cm−1, which covered both P and R branch of the second overtone band of CO. The spectrometer delivers high-resolution surpassing the Fourier-transform resolution limit determined by interferogram length, successfully removing ringing and broadening effects caused by instrumental line shape function. The instrumental-line-shape-free method and high signal-to-noise ratio in the measurement allowed us to observe collisional effects beyond those described by the Voigt profile. We retrieved collisional line-shape parameters by fitting the speed-dependent Voigt profile and found good agreement with the values given by precise cavity ring-down spectroscopy measurements that used a continuous-wave laser referenced to a stabilized OFC. The results demonstrate that OFC-based cavity-enhanced Fourier-transform spectroscopy is a strong tool for accurate line-shape studies that will be crucial for future spectral databases.
Grzegorz Kowzan, Dominik Charczun, Agata Cygan, Ryszard S. Trawiński, Daniel Lisak, and Piotr Masłowski
Springer Science and Business Media LLC
AbstractOptical frequency comb spectrometers open up new avenues of investigation into molecular structure and dynamics thanks to their accuracy, sensitivity and broadband, high-speed operation. We combine broadband direct frequency comb spectroscopy with a dispersive spectrometer providing single-spectrum acquisition time of a few tens of milliseconds and high spectral resolution. We interleave a few tens of such comb-resolved spectra to obtain profiles of 14-kHz wide cavity resonances and determine their positions with precision of a few hertz. To the best of our knowledge, these are the most precise and highest resolution spectral measurements performed with a broadband spectrometer, either comb-based or non-comb-based. This result pushes the limits of broadband comb-based spectroscopy to Hz-level regime. As a demonstration of these capabilities, we perform simultaneous cavity-enhanced measurements of molecular absorption and dispersion, deriving the gas spectra from cavity mode widths and positions. Such approach is particularly important for gas metrology and was made possible by the Hz-level resolution of the system. The presented method should be especially applicable to monitoring of chemical kinetics in, for example, plasma discharges or measurements of narrow resonances in cold atoms and molecules.
Dominik Charczun, Grzegorz Kowzan, Akiko Nishiyama, Przemysław Staniszewski, Agata Cygan, Daniel Lisak, Ryszard S. Trawiński, and Piotr Masłowski
OSA
Agata Cygan, Piotr Wcisło, Szymon Wójtewicz, Grzegorz Kowzan, Mikołaj Zaborowski, Dominik Charczun, Katarzyna Bielska, Ryszard S. Trawiński, Roman Ciuryło, Piotr Masłowski,et al.
The Optical Society
A spectroscopic method free from systematic errors is desired for many challenging applications of gas detection. Although existing cavity-enhanced techniques exhibit very high precision, their accuracy strongly depends on propagation of the light amplitude through an optical system and its detection. Here, we demonstrate that the frequency-based molecular dispersion spectroscopy, involving sub-Hz-level precision in frequency measurements of optical cavity resonances, leads to sub-per-mille accuracy and a wide dynamic range, both previously unattainable by any other spectroscopic technique. The method offers great sensitivity of 5×10-11 cm-1, high speed, limited only by the fundamental response time of the cavity, and traceability of both axes of the spectrum to the primary frequency standard. All these features are necessary for convenient realization of comprehensive molecular spectroscopy from Doppler up to collisional regime without changing the spectroscopic method and modification of the experimental setup. Moreover, the presented approach does not require linear, high-bandwidth nor phase-sensitive detectors and can be directly implemented in existing cavity-enhanced spectrometers utilizing either continuous-wave or coherent broadband radiation. We experimentally prove the predominance of frequency-based spectroscopy over intensity-based one. Our results motivate replacement of intensity-based absorption spectroscopy with a pure frequency-based dispersion one in applications where the highest accuracy is required.
Dominik Charczun, Grzegorz Kowzan, Akiko Nishiyama, Przemyslaw Staniszewski, Agata Cygan, Daniel Lisak, Ryszard S. Trawinski, and Piotr Maslowski
IEEE
Fourier-transform spectroscopy (FTS) over the years has become the golden standard in broadband spectroscopic measurements in the infrared part of the electromagnetic spectrum, offering measurement range limited only by the detector sensitivity and emission spectrum of the light source. This method however has always had a significant tradeoff: it necessitates a mechanical travel scheme to produce an optical path difference (OPD) between interferometer arms, and the spectral resolution is set by this distance, which made the high-resolution measurements very slow and the instrumentation required for them very spacious.
D. Charczun, G. Kowzan, A. Nishiyama, Przemysław Staniszewski, A. Cygan, D. Lisak, R. Trawiński and P. Masłowski
We present a multimodal spectroscopic method employing optical frequency combs, optical cavities and Fourier-transform spectrometry. It allows fast and broadband measurements of both absorption and dispersion spectra as well as of dispersion and reflectivity of mirrors.
Dominik Charczun, Grzegorz Kowzan, Akiko Nishiyama, Przemysław Staniszewski, Agata Cygan, Daniel Lisak, Ryszard S. Trawiński, and Piotr Masłowski
OSA
Dominik Charczun, Grzegorz Kowzan, Akiko Nishiyama, Przemysław Staniszewski, Agata Cygan, Daniel Lisak, Ryszard S. Trawiński, and Piotr Masłowski
OSA