Sub-millisecond Transient Absorption Frequency Comb Spectroscopy in the Mid-Infrared Spectral Region

POSTER

Abstract

The study of highly-reactive transient reaction intermediates is fundamental to understanding chemical dynamics and is particularly relevant to applications such as atmospheric chemistry. Their study often poses a significant challenge for traditional spectrometers, which typically provide broad bandwidth or fast temporal resolution, but not both without long acquisition times. We introduce a cavity-enhanced frequency-comb solution that allows for high-resolution, sensitive spectra to be captured at millisecond intervals in the mid-infrared spectral region using a VIPA dispersive etalon. Once individual comb teeth are resolved, the spectral resolution of the system is limited by the comb linewidth ($<$40 kHz) while the temporal resolution is limited by the minimum integration time of the InSb detector array (10 $\mu$s). In this presentation, I will present the application of this real-time spectroscopic system to small molecule photodissociation.

Authors

  • Bryce Bjork

    • JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics

  • Adam J. Fleisher

    • JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics

  • Thinh Bui

    • Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology

  • Kevin Cossel

    • JILA, NIST and University of Colorado-Boulder, and Department of Physics, University of Colorado-Boulder
    • JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics

  • Mitchio Okumura

    • Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology

  • Jun Ye

    • JILA, NIST, University of Colorado, Boulder
    • JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309, USA
    • JILA/University of Colorado at Boulder
    • JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, CO
    • JILA, University of CO, Boulder and NIST
    • JILA, NIST and University of Colorado-Boulder, and Department of Physics, University of Colorado-Boulder
    • JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics
    • JILA, NIST, and University of Colorado-Boulder