Long-wave mid-infrared cavity-enhanced frequency comb spectroscopy of cold, complex molecules
Optics
2026-02-04 v2 Chemical Physics
Abstract
We report the development of a new instrument for cavity-enhanced absorption spectroscopy of the fundamental rovibrational transitions of molecules in the long-wave mid-infrared (LWIR) region from 6500 to 10000 nm. Our setup combines a LWIR frequency comb, a high-finesse optical enhancement cavity, a cryogenic buffer gas cooling cell, and a Fourier transform interferometer to obtain broadband, high-resolution, and high-sensitivity molecular absorption spectra. Here, we showcase the capabilities of this setup by presenting the gas-phase LWIR spectra of the band of ethane and the band of the gauche conformer of ethanol near 7200 nm under both room temperature and cryogenic conditions.
Keywords
Cite
@article{arxiv.2512.04383,
title = {Long-wave mid-infrared cavity-enhanced frequency comb spectroscopy of cold, complex molecules},
author = {Negar Baradaran and Dominik Charczun and Tanay Nambiar and Meijun Zou and Kevin F. Lee and Martin E. Fermann and Marissa L. Weichman},
journal= {arXiv preprint arXiv:2512.04383},
year = {2026}
}