摘要
Thermal profile modification of an active material in a laser amplifier via optical pumping results in a change in the material’s refractive index,and causes thermal expansion and stress,eventually leading to spatial phase aberrations,or even permanent material damage.For this purpose,knowledge of the 3D spatio-temporal thermal profile,which can currently only be retrieved via numerical simulations,is critical for joule-class laser amplifiers to reveal potentially dangerous thermal features within the pumped active materials.In this investigation,a detailed,spatio-temporal numerical simulation was constructed and tested for accuracy against surface thermal measurements of various endpumped Yb^3+-doped laser-active materials.The measurements and simulations show an excellent agreement and the model was successfully applied to a joule-class Yb3+-based amplifier currently operating in the POLARIS laser system at the Friedrich-Schiller-University and Helmholtz-Institute Jena in Germany.
Thermal profile modification of an active material in a laser amplifier via optical pumping results in a change in the material’s refractive index, and causes thermal expansion and stress, eventually leading to spatial phase aberrations, or even permanent material damage. For this purpose, knowledge of the 3 D spatio-temporal thermal profile, which can currently only be retrieved via numerical simulations, is critical for joule-class laser amplifiers to reveal potentially dangerous thermal features within the pumped active materials. In this investigation, a detailed, spatio-temporal numerical simulation was constructed and tested for accuracy against surface thermal measurements of various endpumped Yb3+-doped laser-active materials. The measurements and simulations show an excellent agreement and the model was successfully applied to a joule-class Yb3+-based amplifier currently operating in the POLARIS laser system at the Friedrich-Schiller-University and Helmholtz-Institute Jena in Germany.
基金
funding from the European Union’s Horizon 2020 Research and Innovation Programme (LASERLAB-EUROPE, Grant No. 654148)
from the European Union (EFRE) through the Thuringian Ministry for Economic Affairs, Science and Digital Society (2016FE9058)
from the Bundesministerium für Bildung und Forschung (BMBF) (03ZIK445, 05P15SJFA1, 03Z1H531 and 03VNE2068D)
