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Dynamics of two laterally coupled semiconductor lasers: strong- and weak-coupling theory
H Erzgräber1, S Wieczorek, B Krauskopf
1School of Engineering, Computing and Mathematics, University of Exeter, Exeter EX4 4QF, United Kingdom.
Summary
We investigated coupled semiconductor laser dynamics using three models. A detailed composite-cavity model accurately captures laser coupling, revealing complex dynamics like chaos, unlike simpler models.
Area of Science:
- Optics and Photonics
- Nonlinear Dynamics
- Semiconductor Physics
Background:
- Semiconductor lasers are crucial for modern optics.
- Understanding coupled laser dynamics is essential for advanced applications.
- Evanescent wave coupling is a key mechanism in miniaturized laser systems.
Purpose of the Study:
- To investigate the stability and nonlinear dynamics of side-coupled semiconductor lasers.
- To compare the accuracy of different modeling approaches for coupled laser systems.
- To elucidate the origins of discrepancies between theoretical models.
Main Methods:
- Developed a composite-cavity model considering electric field profiles.
- Performed bifurcation analysis to map system dynamics.
- Introduced phenomenological and derived coupled-laser models.
- Compared dynamics across different modeling approaches.
Main Results:
- The composite-cavity model accurately represents coupling and reveals diverse dynamics (phase-locking, periodic, quasiperiodic, chaotic).
- Individual-laser models with ad hoc terms show significant deviations from the composite-cavity model.
- A derived coupled-laser model aligns with the composite-cavity model under weak coupling.
Conclusions:
- Model choice critically impacts the prediction of coupled semiconductor laser dynamics.
- Accurate modeling requires detailed consideration of the coupled system's electromagnetic field.
- The derived coupled-laser model offers a more physically grounded approach for weak coupling regimes.
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