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Updated: Apr 6, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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High density terahertz frequency comb produced by coherent synchrotron radiation
11] AILES Beamline, Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, Gif-sur-Yvette 91192, France [2] Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, EA4493 CNRS, 189A Avenue Maurice Schumann, Dunkerque 59140, France.
Nature Communications
|July 21, 2015
Summary
Researchers discovered a powerful terahertz frequency comb from synchrotron radiation. This breakthrough enhances spectroscopy with high precision and signal-to-noise ratio for detailed molecular analysis.
Area of Science:
- Physics
- Spectroscopy
- Metrology
Background:
- Frequency combs have revolutionized spectroscopy and metrology by enhancing resolution and signal-to-noise ratio.
- Synchrotron radiation in coherent mode is known for its intense terahertz continuum.
- The discrete nature of this emission has not been fully characterized.
Purpose of the Study:
- To investigate the spectral characteristics of coherent synchrotron radiation in the terahertz range.
- To demonstrate the potential of this radiation as a frequency comb for high-resolution spectroscopy.
Main Methods:
- Utilizing a dedicated heterodyne receiver to analyze synchrotron radiation.
- Characterizing the frequency comb properties: mode spacing, linewidth, fractional precision, and frequency offset.
Main Results:
- Revealed the purely discrete nature of coherent synchrotron radiation, forming a powerful frequency comb.
- The comb spans over a decade in frequency with a mode spacing of 846 kHz and a linewidth of ~200 Hz.
- Achieved a fractional precision of ~2 × 10⁻¹⁰ with no frequency offset.
Conclusions:
- Coherent synchrotron radiation can act as a powerful frequency comb.
- This terahertz frequency comb offers unprecedented potential for high-resolution spectroscopy.
- Demonstrated its capability by accurately determining pure rotation transitions of acetonitrile.
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