Terahertz Frequency Comb High-Resolution Heterodyne Spectrometer

Francis Hindle (1) , Alexandra Khabbaz (1) , Anthony Roucou (1) , Jean-Francois Lampin , Gaël Mouret (1)

1 LPCA - Laboratoire de Physico-Chimie de l'Atmosphère

We demonstrate the advantages of THz frequency combs for high-resolution spectroscopy. This benefits from wide spectral coverage and the exact knowledge of the frequency position of each comb component. Heterodyne detection combined with a fast Fourier spectrometer enables rapid and simultaneous measurement of more than 80 frequency comb modes covering a 7.5 GHz bandwidth. A spectrum is obtained in under 20 minutes yielding a uniform resolution of 70 kHz. This new setup has been validated by recording more than 150 lines of methanol around 723 GHz, and represents a new solution to exploit THz frequency combs for high-resolution spectroscopy.

Mots clés: Gases; Instruments; Lasers; Laser modes; Spectroscopy; Terahertz radiation; Terahertz wave absorption

Domaines: Instrumentations et Détecteurs [physics.ins-det]

Francis Hindle, Alexandra Khabbaz, Anthony Roucou, Jean-Francois Lampin, Gaël Mouret. Terahertz Frequency Comb High-Resolution Heterodyne Spectrometer. 2024. ⟨hal-04811272⟩