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Updated: Jun 22, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
Passive Q-switching characteristics of Yb3+:Gd3Ga5O12 crystal
Abstract:
The passively Q-switched laser characteristics of a quasi-three level Yb3+:Gd3Ga5O12 (Yb3+:GGG) crystal with Cr4+:YAG saturable absorbers are studied experimentally and theoretically. The pulse parameters under different experimental conditions are measured. Some characteristics different from those of a four-level system are found. In the theoretical aspect, taking into account the spatial distributions of the pump light and intracavity laser mode, the rate equations describing the single Q-switched pulse characteristics of a quasi-three-level system are obtained. The obtained theoretical results are in fair agreement with the experimental results. Some topics such as the influence of the pumping power, the selection of the pump beam size, the optimal combination of output coupler reflectivity and saturable absorber initial transmission, the influence of the excited absorption of the saturable absorber, are discussed.
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