DESIREE&Friends 12 - Molecular spectroscopy using optical frequency combs

by Prof. Aleksandra Foltynowicz (Umeå University)

Thursday 15 Oct 2026, 13:00 → 13:45 Europe/Stockholm

FB51 (AlbaNova Main Building)

Optical frequency combs are broadband laser sources whose spectra consist of hundreds of thousands of evenly spaced frequencies traceable to fundamental frequency standards. This unique combination of high spectral resolution, absolute frequency accuracy, and broad spectral coverage has revolutionized molecular spectroscopy. We use Fourier transform spectroscopy based on near- and mid-infrared frequency combs to provide highly accurate spectroscopic data for molecules relevant to environmental monitoring and astrophysics. One example is methane – the first organic molecule detected in the atmosphere of a hot-Jupiter exoplanet – whose highly excited vibrational energy level structure remains incompletely characterized. I will show how frequency comb spectroscopy combined with state-of-the-art theoretical predictions identifies and assigns highly excited vibrational levels, providing essential data for accurate modeling of high-temperature spectra in astrophysics.