Eichhorn, MarcRupp, MariusMariusRupp2025-11-112025-11-112025https://publica.fraunhofer.de/handle/publica/49905010.5445/IR/1000179649Advancements in solid-state laser technology have enabled their use in various fields. In this work, a multi-physics modeling approach is developed for high-power bulk lasers, allowing for the analysis of otherwise inaccessible quantities and processes. The model consists of three submodels: laser beam propagation, laser gain, and thermal effects. The accuracy of the simulation is increased through various methods. The developed model is validated by designing experimental Ho3+:YAG systems.endoctoral thesis