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Chirped-pulse terahertz spectroscopy for broadband trace gas sensing



Eyal Gerecht, Kevin O. Douglass, David F. Plusquellic


We report the first demonstration of a broadband trace gas sensor based on chirp-pulse terahertz spectroscopy. The advent of newly developed solid state sources and heterodyne detectors for the terahertz frequency range have made it possible to generate and detect precise arbitrary waveforms at THz frequencies with ultra-low phase noise. In order to maximize sensitivity, the sample gas is first polarized using a sub-μsec chirped THz pulse and the free inductive decay (FID) is detected using a heterodyne receiver. This approach allows for a rapid broadband multi-component sensing with parts-per-billion sensitivity at a spectral resolution of
Optics Express


chirped pulse, free induction decay, phase stable, THz amplifier multiplier chains, trace gas detector


Gerecht, E. , Douglass, K. and Plusquellic, D. (2011), Chirped-pulse terahertz spectroscopy for broadband trace gas sensing, Optics Express, [online], (Accessed May 26, 2024)


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Created April 22, 2011, Updated January 27, 2020