ISBN 9783843902984

978-3-8439-0298-4, Reihe Ingenieurwissenschaften

Matthias Wohlmuth
Modeling and Simulation of Solid-State Laser Resonators Using a Dynamic Multimode Analysis (DMA)

216 Seiten, Dissertation Universität Erlangen-Nürnberg (2011), Hardcover, B5

Zusammenfassung / Abstract

This dissertation deals with the modeling and simulation of solid-state laser resonators. Its primary focus is on the derivation of suitable physical models and their implementation in a multi-physics simulation. As a result, the dynamic and spatial properties of the laser beam can be characterized comprehensively in terms of measurable parameters such as output power, pulse duration, and beam quality. The core of the simulation model consists of the Dynamic Multimode Analysis (DMA), which predicts the dynamic oscillation behavior of the resonator eigenmodes.

In this thesis, the basic laser principles are reviewed on a quantum mechanical level to derive the theoretical foundations of DMA. Then, DMA multimode rate equations for 4-level and quasi 3-level lasers are discussed together with modeling aspects such as mode coherence and mode interference. A method for including thermal lensing, intra-cavity optics, Q-switching, aperture losses, and super-Gaussian output couplers in the simulation is explained. Furthermore, a model extension based on generalized mode structures for lasers with extremely high multimode content is presented.

The DMA has been successfully applied to a variety of laser systems and the simulation results have been used to improve their designs. Numerical results for a selection of resonator configurations are analyzed theoretically and validated with experimental data.

In conclusion, the Dynamic Multimode Analysis (DMA) presented here overcomes existing barriers of current state-of-the-art multi-physics laser simulations. In particular, it predicts the dynamic behavior of the laser beam including its beam quality. Thus, DMA proves to be a comprehensive simulation approach and its implementation provides a powerful and efficient tool for the simulation and optimization of solid-state laser resonators.