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Coherent beam combining: optical loss effects on power scaling
Applied Optics
|November 10, 2010
Summary
A new model simulates multi-stage amplifier arrays with pairwise beam combining. Coherent-combining losses significantly reduce system efficiency and increase size.
Area of Science:
- Optics and Photonics
- Laser Technology
- Optical Engineering
Background:
- Coherent beam combining (CBC) is crucial for high-power laser systems.
- Modeling amplifier arrays requires accounting for various loss mechanisms.
- Understanding efficiency limitations is key for system design.
Purpose of the Study:
- To develop a comprehensive model for multi-stage amplifier arrays utilizing pairwise beam combining.
- To analyze the impact of gain saturation, optical-coupling, and combining efficiencies on system performance.
- To identify the dominant factors affecting system size and efficiency.
Main Methods:
- Developed a mathematical model for a multi-stage amplifier array with final-stage pairwise beam combining.
- Incorporated gain saturation, optical-coupling losses, and coherent-combining efficiency into the model.
- Derived individual amplifier parameters from experimental data.
- Calculated system size, efficiency, and output power as functions of key efficiencies.
Main Results:
- The model accurately predicts system performance based on experimental amplifier data.
- Optical-coupling efficiency and coherent-combining efficiency were found to be critical parameters.
- Exponential losses from pairwise beam combining were identified as the primary cause of efficiency reduction.
Conclusions:
- Coherent-combining losses are the dominant factor limiting the efficiency of multi-stage amplifier arrays.
- System size increases exponentially with decreasing combining efficiency.
- The developed model provides a valuable tool for designing and optimizing high-power laser systems.
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