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arXiv · 2412.01308

Terahertz Frequency Comb High-Resolution Heterodyne Spectrometer

Francis Hindle·Alexandra Khabbaz·Anthony Roucou·Jean-Francois Lampin·Gaël Mouret
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Abstract

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.

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Francis Hindle, Alexandra Khabbaz, Anthony Roucou, Jean-Francois Lampin, Gaël Mouret. 2024-12-02. Terahertz Frequency Comb High-Resolution Heterodyne Spectrometer. https://arxiv.org/abs/2412.01308

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