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Updated: May 16, 2026
09:38
Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Subkilohertz linewidth room-temperature mid-infrared quantum cascade laser using a molecular sub-Doppler reference.
1CNR-INO-Istituto Nazionale di Ottica, Firenze 50125, Italy. francesco.cappelli@ino.it
Optics Letters
|December 4, 2012
Summary
We narrowed a room-temperature mid-infrared quantum cascade laser
Area of Science:
- Quantum optics
- Laser physics
- Spectroscopy
Background:
- Room-temperature mid-infrared quantum cascade lasers (QCLs) are crucial for various applications.
- Achieving narrow linewidths and frequency stabilization in these lasers remains a challenge.
Purpose of the Study:
- To narrow the linewidth and stabilize the frequency of a room-temperature mid-IR quantum cascade laser.
- To demonstrate frequency locking to a CO2 sub-Doppler transition.
Main Methods:
- Utilized polarization spectroscopy to obtain a CO2 sub-Doppler transition.
- Employed frequency locking techniques to stabilize the QCL.
- Achieved a locking bandwidth of 250 kHz.
Main Results:
- Narrowed the laser linewidth by over two orders of magnitude, achieving sub-kHz linewidth.
- Stabilized the absolute frequency of the laser to sub-kHz precision.
- Demonstrated effective frequency locking to the CO2 transition.
Conclusions:
- Frequency locking to a CO2 sub-Doppler transition is an effective method for narrowing and stabilizing mid-IR QCLs.
- The achieved sub-kHz linewidth and frequency stability open possibilities for high-precision spectroscopy and sensing.
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