Frequency stable and low phase noise THz synthesis for precision spectroscopy
As part of the ANR Meteorit program supported by the CNRS, a robust approach to generating very high-purity THz waves has been evaluated over a very wide band, in this case with tunability from 0.1 THz to 1.4 THz. This low-phase-noise generator has a frequency drift of the order of a few mHz/s, making it particularly suitable for spectroscopic measurements, but also as a stable, pure carrier wave for very high-speed THz transmissions.
The recently published article is an experimental demonstration of its use for highly accurate gas-phase molecular spectroscopy measurements. The scientific community needs this kind of performance to assess the space-time stability of fundamental constants, which is the aim of the above-mentioned ANR project.
Measurement of a linewidth invariant from 2 to 1200 GHz with the developed source.
The use of this type of THz source for telecoms is also planned, in order to invest in high spectral efficiency modulation formats (bit/s/Hz).
Djevahirdjian, L., Lechevallier, L., Martin-Drumel, MA. et al. Frequency stable and low phase noise THz synthesis for precision spectroscopy. Nat Commun 14, 7162 (2023). https://doi.org/10.1038/s41467-023-42905-z
