Related papers: Intracavity trace molecular detection with a broad…
The development of a multiple-channel lock-in optical spectrometer (LIOS) is presented, which enables parallel phase-sensitive detection at the output of an optical spectrometer. The light intensity from a spectrally broad source is…
A mid-infrared laser-based sensor is designed and demonstrated for trace detection of benzene, acetylene, and carbon dioxide at ambient conditions. The sensor is based on a distributed feedback quantum cascade lase and a multidimensional…
Mid-infrared light scatters much less than shorter wavelengths, allowing greatly enhanced penetration depths for optical imaging techniques such as optical coherence tomography (OCT). However, both detection and broadband sources in the…
Molecular diagnostics are a primary tool of modern chemistry, enabling researchers to map chemical reaction pathways and rates to better design and control chemical systems. Many chemical reactions are complex and fast, and existing…
We describe a coherent mid-infrared continuum source with 700 cm-1 usable bandwidth, readily tuned within 600 - 2500 cm-1 (4 - 17 \mum) and thus covering much of the infrared "fingerprint" molecular vibration region. It is based on…
Dual-comb spectroscopy allows for the rapid, multiplexed acquisition of high-resolution spectra without the need for moving parts or low-resolution dispersive optics. This method of broadband spectroscopy is most often accomplished via…
Mid-infrared optical frequency combs are of significant interest for molecular spectroscopy due to the large absorption of molecular vibrational modes on one hand, and the ability to implement superior comb-based spectroscopic modalities…
We present and characterize a 2-D imaging spectrometer based on a virtually-imaged phased array (VIPA) disperser for rapid, high-resolution molecular detection using mid-infrared (MIR) frequency combs at 3.1 and 3.8 \mu m. We demonstrate…
We investigate the presence of COMs in strongly UV-irradiated interstellar molecular gas. We have carried out a complete millimetre line survey using the IRAM30m telescope towards the edge of the Orion Bar photodissociation region (PDR),…
As a potent greenhouse gas and ozone depleting agent, nitrous oxide (N$_2$O) plays a critical role in the global climate. Effective mitigation relies on understanding global sources and sinks which can be supported through isotopic…
Spectroscopy in the molecular fingerprint spectral region (6.5-20 $\mu$m) yields critical information on material structure for physical, chemical and biological sciences. Despite decades of interest and effort, this portion of the…
Frequency combs, spectra of evenly-spaced narrow phase-coherent laser lines, have revolutionized precision measurements. On-chip frequency comb generators hold much promise for fully-integrated instruments of time and frequency metrology.…
We have built a frequency chain which enables to measure the absolute frequency of a laser emitting in the 28-31 THz frequency range and stabilized onto a molecular absorption line. The set-up uses an optical frequency comb and an…
Optical frequency combs have revolutionized precision measurement, time-keeping, and molecular spectroscopy. A substantial effort has developed around "microcombs": integrating comb-generating technologies into compact, reliable photonic…
We propose a direct and real-time ranging scheme using an optical frequency combs, able to compensate optically for index of refraction variations due to atmospheric parameters. This scheme could be useful for applications requiring…
We report a broadband long-wave infrared Fourier transform spectrometer with sensitivity exceeding that of previously reported direct-detection implementations. The system combines dual-comb spectroscopy with electro-optic sampling,…
High resolution and fast detection of molecular vibrational absorption is important for organic synthesis, pharmaceutical process and environmental monitoring, and is enabled by mid-infrared (mid-IR) laser frequency combs via dual-comb…
We propose and characterize experimentally a new source of optical frequency combs for performing multi-heterodyne spectrometry. This comb modality is based on a frequency shifting loop seeded with a CW monochromatic laser. The comb lines…
A fully stabilized mid-infrared optical frequency comb spanning from 2.9 to 3.4 um is described. The comb is based on half-harmonic generation in a femtosecond optical parametric oscillator, which transfers the high phase coherence of a…
We demonstrate fast characterization (~1.4 microseconds) of both the dispersion and dispersion slope of long optical fiber links (~25 km) using dual quadrature spectral interferometry with an optical frequency comb. Compared to previous…