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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Impact of higher-order dispersion on frequency-modulated combs
Optics Letters
|February 15, 2024
Summary
Higher-order dispersion in semiconductor lasers degrades frequency-modulated (FM) combs. Applying radio frequency modulation to the laser bias or electrical injection-locking significantly improves FM comb performance for spectroscopy.
Area of Science:
- Optics and Photonics
- Laser Physics
- Spectroscopy
Background:
- Frequency-modulated (FM) combs are generated in semiconductor lasers and are promising for spectroscopy.
- Existing theoretical models are advanced, but experimental FM combs often show non-ideal characteristics, limiting their practical application.
- Higher-order dispersion effects are suspected contributors to these experimental limitations.
Purpose of the Study:
- To theoretically and experimentally investigate the impact of higher-order dispersion on FM comb generation in semiconductor lasers.
- To identify methods for mitigating detrimental effects of dispersion on FM comb properties.
- To enhance the performance of FM combs for improved spectroscopic applications.
Main Methods:
- Theoretical modeling of FM comb formation considering higher-order dispersion.
- Experimental generation and characterization of FM combs in semiconductor lasers.
- Application of radio frequency (RF) modulation to the laser bias.
- Implementation of electrical injection-locking techniques.
Main Results:
- Spectrally dependent dispersion was identified as a key factor degrading comb bandwidth and causing spectral holes.
- RF modulation of the laser bias effectively suppressed these undesirable traits.
- Electrical injection-locking significantly broadened the comb bandwidth, flattened spectral amplitudes, and linearized the frequency chirp.
Conclusions:
- Higher-order dispersion is a critical factor limiting the performance of experimental FM combs.
- RF modulation and electrical injection-locking are effective strategies to overcome dispersion-induced limitations.
- Optimized FM combs exhibit enhanced bandwidth, spectral uniformity, and linear chirp, making them more suitable for advanced spectroscopic applications.
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