@inproceedings{6ead5c966b264a24a6a89d4fdef768d5,
title = "Comb tooth resolved MIR spectroscopy using a VECSEL frequency comb and a virtually-imaged phased array spectrometer",
abstract = "Mid infrared frequency combs allow for high resolution absorption spectroscopy of molecular species, which have strong signatures in this spectral region. Dual comb spectroscopy can provide broadband and high-resolution capability, but requires two fully stabilized frequency combs which adds complexity to the system. Previous work has demonstrated that frequency combs coupled with a high resolution spectrometer, consisting of a virtually imaged phased array (VIPA) along with a grating, can perform time-resolved, broadband and high- resolution absorption spectroscopy with a single frequency comb. The VIPA spectrometer disperses the spectrum in two dimensions and images it onto a focal plane detector array. If the comb teeth can be resolved, the VIPA is easily calibrated and provides comb-tooth resolved resolution and accuracy. However, in previous work, the repetition rate of the laser sources used was too low to be resolved directly, and additional passive {"}filter cavities{"} had to be employed to increase the effective repetition rate of the frequency comb. In this work we use a fully stabilized mid infrared frequency comb based on a 1.6 GHz repetition rate modelocked vertical external cavity surface emitting laser (VECSEL) and difference frequency generation to produce an off set free comb in the 3- 4 micron wavelength range. The source is directly coupled to the VIPA spectrometer to provide comb-tooth resolved absorption spectroscopy. We discuss the system's performance in gas absorption spectroscopy and its time resolving capabilities, which are limited only by the speed of the detector system.",
keywords = "Difference frequency generation, Frequency comb, GHz, Methane, Mid-infrared, Spectroscopy, VECSEL, VIPA",
author = "Robert Rockmore and Ricky Gibson and Jones, {R. Jason} and Moloney, {Jerome V.}",
note = "Funding Information: We thank Robert Bedford of AFRL for technical discussions on the experiments. We would like to thank Scott Diddams, Scott Papp, David Carlson, Daniel Hickstein, and Connor Fredrick at NIST for technical discussions and use of the SiN waveguides and VIPA etalon. We also thank Wolfgang Stolz and Antje Ruiz Perez at Philipps Universitat, Marburg for growing our VECSEL structures, and Ganesh Balakrishnan and Sadhvikas Addamane at the University of New Mexico for growing our SESAMs. This material is based upon work supported by the Air Force Office of Scientific Research under award ID FA9550-17-1-0246. Publisher Copyright: {\textcopyright} COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.; Vertical External Cavity Surface Emitting Lasers (VECSELs) X 2020 ; Conference date: 04-02-2020 Through 05-02-2020",
year = "2020",
doi = "10.1117/12.2546752",
language = "English (US)",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Hastie, {Jennifer E.}",
booktitle = "Vertical External Cavity Surface Emitting Lasers (VECSELs) X",
}