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Updated: Jun 22, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Ultra-stable, widely tunable and absolutely linked mid-IR coherent source
I Galli1, S Bartalini, P Cancio
1Istituto Nazionale di Ottica Applicata- CNR, Firenze, FI, Italy.
Optics Express
|June 10, 2009
Summary
Researchers developed a new tunable coherent source with a 10-Hz linewidth. This precise optical frequency tool enhances molecular physics research by achieving high absorption sensitivity.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Spectroscopy
- Quantum Optics
Background:
- Precise frequency control is crucial for advanced molecular spectroscopy.
- Existing coherent sources often lack the required tunability or linewidth for certain applications.
Purpose of the Study:
- To develop a novel coherent source with exceptional spectral characteristics.
- To demonstrate its capability for high-sensitivity absorption measurements.
Main Methods:
- Implementing a phase-lock scheme to an optical frequency-comb synthesizer.
- Coupling the source to a high-finesse optical cavity.
- Tuning the source across the 4–4.5 micrometer wavelength range.
Main Results:
- Achieved a 10-Hz intrinsic linewidth for the coherent source.
- Demonstrated presettable absolute frequency control.
- Obtained a short-term absorption sensitivity of 1.3 x 10(-11) cm(-1)Hz,(-1/2) when cavity-enhanced.
Conclusions:
- The developed coherent source offers unique spectral features for precision measurements.
- It serves as a powerful tool for molecular physics and spectroscopy.
- The high sensitivity enables new possibilities in trace gas detection and fundamental studies.
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