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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Frequency noise in frequency swept fiber laser
Anders Tegtmeier Pedersen1, Karsten Rottwitt
1Department of Photonics Engineering, Technical University of Denmark, Lyngby, Denmark. antp@fotonik.dtu.dk
Optics Letters
|April 3, 2013
Summary
This study precisely measured frequency-shifted pulses from a synthesized lightwave sweeper. Key findings include high accuracy in frequency shifts and the presence of noise from acousto-optic modulators and Brillouin scattering.
Area of Science:
- Optics and Photonics
- Spectroscopy
Background:
- Frequency-agile light sources are crucial for advanced optical systems.
- Characterizing the spectral content of frequency-shifted pulses is essential for understanding their behavior.
Purpose of the Study:
- To measure the spectral content of frequency-shifted pulses generated by a lightwave synthesized frequency sweeper.
- To assess the accuracy of frequency shifting.
- To identify sources of noise in the generated spectrum.
Main Methods:
- Utilized a lightwave synthesized frequency sweeper to generate frequency-shifted pulses.
- Performed spectral analysis to determine the frequency content of individual pulses.
- Investigated noise contributions from optical components and scattering phenomena.
Main Results:
- Demonstrated highly accurate frequency shifting for each generated pulse.
- Identified spectral noise originating from light leakage through acousto-optic modulators.
- Observed spectral signatures of forward propagating Brillouin scattering.
Conclusions:
- The lightwave synthesized frequency sweeper provides precise frequency control.
- Acousto-optic modulator leakage and Brillouin scattering are significant noise sources affecting spectral purity.
- Understanding these spectral characteristics is vital for optimizing optical system performance.
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