Related Experiment Video
Updated: May 24, 2026
09:38
Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Heterodyne beatings between frequency-shifted feedback lasers
Hugues Guillet de Chatellus1, Eric Lacot, Olivier Jacquin
1CNRS/Université Grenoble 1, Laboratoire Interdisciplinaire de Physique, UMR 5588, Grenoble F-38041, France. hguillet@ujf‑grenoble.fr
Optics Letters
|March 2, 2012
Summary
Frequency-shifted feedback (FSF) lasers exhibit beatings in their noise spectrum, useful for long-distance telemetry. These beatings also appear when mixing two distinct FSF lasers, enabling characterization of laser time-spectrum properties.
Area of Science:
- Optics and Photonics
- Laser Physics
- Telecommunications
Background:
- Frequency-shifted feedback (FSF) lasers show promise for long-distance telemetry.
- Beatings in the noise spectrum of homodyne interferometers vary linearly with path delay.
Purpose of the Study:
- To demonstrate beatings in the heterodyne mixing of two distinct FSF lasers.
- To exploit this phenomenon for characterizing FSF laser time-spectrum properties.
- To present consequences for FSF laser telemetry.
Main Methods:
- Heterodyne mixing of two identical, distinct FSF lasers.
- Analysis of the noise spectrum for beatings.
- Application of the passive cavity model for explanation.
Main Results:
- Beatings are observed in the heterodyne mixing of two distinct FSF lasers.
- The passive cavity model successfully explains the observed beatings.
- The phenomenon allows for characterization of FSF laser time-spectrum properties.
Conclusions:
- The occurrence of beatings in heterodyne mixing extends the applicability of FSF lasers.
- FSF laser characterization is enhanced through this beatings phenomenon.
- This finding has significant implications for the future of long-distance telemetry using FSF lasers.
