Abstract
Vernier spectroscopy is a frequency comb-based technique employing optical cavities for filtering of the comb and for enhancement of the interaction length with the sample. Depending on the ratio of the cavity free spectral range and the comb repetition rate, the cavity transmits either widely spaced individual comb lines (comb-resolved Vernier spectroscopy) or groups of comb lines, called Vernier orders (continuous-filtering Vernier spectroscopy, CF-VS). The cavity filtering enables the use of low-resolution spectrometers to resolve the individual comb lines or Vernier orders. Vernier spectroscopy has been implemented using various near-and mid-infrared comb sources for applications ranging from trace gas detection to precision spectroscopy. Here, we present the principles of the technique and provide a review of previous demonstrations of comb-resolved and continuous-filtering Vernier spectroscopy. We also demonstrate two new implementations of CF-VS: one in the mid-infrared, based on a difference frequency generation comb source, with a new and more robust detection system design, and the other in the near-infrared, based on a Ti:sapphire laser, reaching high sensitivity and the fundamental resolution limit of the technique.
Original language | English |
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Article number | 222 |
Journal | Photonics |
Volume | 9 |
Issue number | 4 |
DOIs | |
Publication status | Published - Apr 2022 |
MoE publication type | A2 Review article in a scientific journal |
Funding
Funding: This research was funded by the Knut and Alice Wallenberg Foundation, grant number KAW 2015.0159 and by the CNRS program “Défi Instrumentation aux Limites”, grant number 154957.
Keywords
- cavity enhanced spectroscopy
- frequency comb spectroscopy
- precision spectroscopy
- trace gas detection
- Vernier spectroscopy