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Updated: Jun 7, 2025
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
16.9K
Exceptional point proximity-driven mode-locking in coupled microresonators.
Optics Express
|November 14, 2024
Summary
Mode-locking is achieved in coupled-cavity systems without a saturable absorber. A lossy cavity acts as an artificial saturable absorber near an exceptional point, enabling efficient mode-locking.
Area of Science:
- Photonics and Optical Engineering
- Nonlinear Optics
- Quantum Optics
Background:
- Mode-locking is crucial for generating ultrashort optical pulses.
- Conventional mode-locking often relies on saturable absorbers, which can be complex to integrate.
- Exceptional points in open systems offer unique phenomena for optical control.
Purpose of the Study:
- To demonstrate theoretically and numerically the feasibility of mode-locking in coupled-cavity systems.
- To introduce a novel approach using an artificial saturable absorber.
- To highlight the advantages of this new method over traditional techniques.
Main Methods:
- Theoretical analysis of coupled-cavity systems with gain and loss.
- Numerical simulations to verify mode-locking conditions.
- Investigation of system Q-factor modulation near exceptional points.
Main Results:
- Mode-locking is achievable without a natural saturable absorber.
- Exceptional points lead to significant Q-factor modulation with minimal nonlinear effects.
- A lossy auxiliary cavity effectively functions as an artificial saturable absorber.
Conclusions:
- A novel, efficient method for mode-locking in coupled-cavity systems is presented.
- This approach offers reduced operational power and easier post-adjustment.
- The use of exceptional points and artificial absorbers opens new avenues in laser design.
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