Understanding how light amplifies within fibre lasers is crucial for developing more powerful and efficient laser technologies, and researchers are continually seeking ways to model this process accurately and quickly. Rebecca Bryant from Portland State University, Jacob Grosek from the Air Force Research Laboratory, and Jay Gopalakrishnan from Portland State University, have now developed a significantly accelerated model for fibre laser amplifiers, grounded in a rigorous mathematical framework. Their work applies established principles of dynamical systems to the well-known coupled mode theory, resulting in a model that runs much faster than existing simulations while maintaining high accuracy in critical performance metrics like output power and amplification efficiency. This advancement not only speeds up the design process for laser amplifiers, but also expands the range of amplifier types and configurations that can be effectively modelled, representing a substantial step forward in laser technology development.
Simplified Modeling of Fiber Laser Amplifiers
Scientists have developed a rigorous mathematical framework for simplifying complex models of fiber laser amplifiers, overcoming limitations in existing approximations and enabling faster simulations. This work centers on applying a generalized averaging theorem, originally established by Sanders, Velhurst, and Murdock, to the coupled mode theory (CMT) model commonly used to describe these amplifiers. This theorem justifies neglecting high-frequency oscillatory terms within the model, significantly reducing computational demands while maintaining accuracy. The team extended the original theorem to accommodate complex-valued vector spaces and sums of periodic functions, essential for accurately representing the amplifier’s behavior.
To validate their approach, researchers reproduced the key theorem, adapting it to handle the specific complexities of the fiber amplifier model. They then demonstrated that the averaged system yields solutions with bounded error compared to the original model. This averaging technique effectively filters out high-frequency components, allowing for fewer discrete points in numerical simulations and satisfying Nyquist’s sampling theorem. A crucial aspect of the work involves establishing criteria for the theorem’s validity, specifically requiring that the functions describing the amplifier’s behavior are Lipschitz continuous and that the system remains bounded during simulation.
The team rigorously quantified the error introduced by the averaging process, deriving a constant that defines the maximum deviation between the original and averaged solutions. Through careful analysis, scientists demonstrated that the averaged CMT model achieves a 0. 2 increase in computational speed compared to the full CMT model, while preserving key performance metrics such as output power and amplification efficiency. This advancement enables more efficient design and optimization of fiber laser amplifiers, paving the way for more powerful and versatile laser technologies.
Accelerated Amplifier Model Achieves 4000x Speedup
This work presents a new accelerated model for simulating optical fiber amplifiers, building upon the established coupled mode theory (CMT) approach and leveraging techniques from dynamical systems. Scientists achieved a remarkable 4000x increase in computational speed compared to the standard CMT model, while maintaining high accuracy in critical performance metrics such as output power and amplification efficiency. This breakthrough stems from applying a theorem for simplifying dynamical systems with bounded error, providing a mathematically rigorous foundation for approximations commonly used in the field. The research team developed an accelerated model, which significantly reduces computational demands without compromising the fidelity of key amplifier characteristics.
The improvement in speed allows for more complex amplifier designs to be modeled and optimized, potentially leading to advancements in laser technology and optical communications. Furthermore, the study argues that the approximations within the model broaden its applicability to a wider variety of amplifier types and configurations than existing reduced models. This enhanced versatility makes the model a valuable asset for researchers and engineers working on diverse optical fiber technologies.
Accelerated Amplifier Simulation via Dynamical Systems Theory
This work presents a new accelerated model for simulating optical fiber amplifiers, building upon the established coupled mode theory approach. Researchers successfully applied a theorem for simplifying dynamical systems to this specific problem, providing a mathematically rigorous foundation for approximations commonly used in the field. Testing demonstrates that this accelerated model achieves a substantial increase in computational speed, approximately 4000times faster than the standard model, while maintaining high accuracy in key performance indicators such as output power and amplification efficiency. The resulting model expands the range of amplifier types and configurations that can be effectively simulated, surpassing the limitations of currently available reduced models.
👉 More information
🗞 Accelerated Coupled Mode Model for Fiber Laser Amplifiers as an Averaged Dynamical System
🧠 ArXiv: https://arxiv.org/abs/2511.20981
