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Effect of phase-conjugate feedback on semiconductor laser dynamics.
Optics Letters
|September 25, 2009
Summary
Phase-conjugate feedback in semiconductor lasers can lead to instabilities and chaotic output. The study identifies fold and Hopf instabilities, with chaos emerging via period-doubling or quasi-periodic routes.
Area of Science:
- Optics and Photonics
- Nonlinear Dynamics
- Semiconductor Device Physics
Background:
- Semiconductor lasers are crucial optoelectronic devices.
- Understanding their dynamic response under feedback is essential for applications.
- Phase-conjugate feedback introduces unique nonlinear effects.
Purpose of the Study:
- To investigate the impact of phase-conjugate feedback on semiconductor laser dynamics.
- To identify the conditions leading to instability and chaotic behavior.
- To analyze the routes to chaos in such systems.
Main Methods:
- Utilized a rate-equation approach to model laser dynamics.
- Analyzed the stability of the steady state under phase-conjugate feedback.
- Investigated the role of fold and Hopf instabilities.
Main Results:
- Steady-state solutions exist only for specific intracavity optical field phases.
- Phase-conjugate feedback induces fold and Hopf instabilities, destabilizing the steady state.
- The fold instability is unique to phase-conjugate feedback.
- Laser output exhibits chaotic behavior through period-doubling or quasi-periodic routes.
Conclusions:
- Phase-conjugate feedback significantly alters semiconductor laser dynamics.
- The identified instabilities provide insights into the onset of chaos.
- The study elucidates the complex routes to chaotic emission in these lasers.
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