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