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Updated: Feb 21, 2026
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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
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Measuring molecular frequencies in the 1-10 μm range at 11-digits accuracy
G Insero1,2, S Borri1,2, D Calonico3
1Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.
Scientific Reports
|October 8, 2017
Summary
Researchers developed a new high-resolution spectroscopy setup covering 1-10 μm. This system uses quantum cascade lasers and difference frequency generation for precise measurements, overcoming previous limitations in tunability and accuracy.
Area of Science:
- Quantum optics
- Spectroscopy
- Laser technology
Background:
- High-resolution spectroscopy in the 1-10 μm range is limited by practical light source constraints.
- Existing methods face challenges with spectral range, power, and frequency accuracy.
Purpose of the Study:
- To present a novel, widely-tunable, and accurate light source setup for high-resolution spectroscopy.
- To enable spectroscopy across the entire 1-10 μm spectral region.
Main Methods:
- Combining quantum cascade lasers (QCLs) with difference frequency generation (DFG).
- Utilizing an orientation-patterned GaP crystal for DFG.
- Measuring frequency against a primary standard via a metrological fiber link.
Main Results:
- Demonstrated a high-resolution spectroscopy setup applicable across the 1-10 μm range.
- Achieved high precision frequency measurements.
- Measured a CO vibrational transition around 6 μm with 11-digit accuracy.
Conclusions:
- The developed setup overcomes limitations of previous light sources for mid-infrared spectroscopy.
- This approach offers a practical and accurate solution for high-resolution measurements in the 1-10 μm region.
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