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Published on: December 18, 2015
Frequency versus relaxation oscillations in a semiconductor laser with coherent filtered optical feedback
H Erzgräber1, B Krauskopf, D Lenstra
1Afdeling Natuurkunde en Sterrenkunde, Vrije Universiteit Amsterdam, The Netherlands.
Summary
Semiconductor lasers with optical feedback exhibit two stable oscillation types: relaxation and external roundtrip. Feedback phase controls complex dynamics, enabling pure frequency oscillations in specific regions.
Area of Science:
- Nonlinear dynamics
- Semiconductor laser physics
- Optical engineering
Background:
- Semiconductor lasers are crucial optoelectronic devices.
- Understanding their dynamic behavior under optical feedback is essential for applications.
- Previous studies have explored various feedback regimes, but a systematic analysis of coherent delayed filtered feedback is needed.
Purpose of the Study:
- To systematically analyze the dynamical behavior of a semiconductor laser under coherent delayed filtered optical feedback.
- To identify and characterize the different types of stable oscillations supported by the system.
- To investigate the role of feedback parameters, particularly the feedback phase, in controlling the system's dynamics.
Main Methods:
- Bifurcation analysis was employed to systematically explore the parameter space.
- The study focused on variations in feedback conditions, including feedback strength and phase.
- Numerical simulations were used to observe and confirm the predicted dynamical states.
Main Results:
- The semiconductor laser system exhibits two distinct types of stable oscillations: relaxation oscillations and external roundtrip oscillations.
- Stable domains for both oscillation types were identified across a range of feedback conditions.
- The feedback phase was found to be a critical parameter for controlling the system's complex dynamics.
- Two specific parameter regions were identified where stable external roundtrip oscillations occur as pure frequency oscillations.
Conclusions:
- Coherent delayed filtered optical feedback introduces significant dynamical complexity into semiconductor laser behavior.
- The system's dynamics can be effectively controlled by adjusting the feedback phase, leading to distinct oscillation regimes.
- The identification of stable pure frequency oscillations in specific parameter regions offers potential for advanced laser applications requiring precise frequency control.
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