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06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Observation of noise phase locking in a single-frequency VECSEL
A El Amili1, V Pal, F Goldfarb
1Laboratoire Aimé Cotton, CNRS-Université Paris Sud 11, Campus d'Orsay, Orsay, France.
Optics Express
|September 22, 2011
Summary
We observed phase locking in semiconductor laser intensity noise. Coherent oscillations between laser modes create noise correlations, modifying the noise spectrum near the free-spectral-range. This reveals new insights into laser dynamics.
Area of Science:
- Optics and Photonics
- Semiconductor Physics
Background:
- Semiconductor lasers exhibit complex noise spectra.
- Understanding noise correlations is crucial for laser applications.
- Mode interactions significantly influence laser output characteristics.
Purpose of the Study:
- To experimentally observe phase locking effects in semiconductor laser intensity noise.
- To investigate the role of carrier-population oscillations in noise generation.
- To analyze modifications in the intensity noise spectrum due to mode interactions.
Main Methods:
- Experimental observation of intensity noise spectrum.
- Inducing coherent carrier-population oscillations via mode beatnotes.
- Varying the relative phase shift between lasing and non-lasing modes.
Main Results:
- Demonstrated phase locking effects in the intensity noise spectrum.
- Identified noise correlations arising from coherent carrier-population oscillations.
- Observed spectral modifications around the cavity free-spectral-range.
Conclusions:
- Phase locking of laser modes leads to observable noise correlations.
- Carrier dynamics play a key role in shaping laser noise profiles.
- Experimental evidence supports the influence of mode interactions on laser noise spectra.
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