Thermal lens analysis in a diode-pumped 10 Hz 100 mJ Yb:YAG amplifier

Victor Hariton; Celso Paiva Jo?o; Hugo Pires; Mario Galletti; Gon?alo Figueira

doi:10.1017/hpl.2020.11

Journals >High Power Laser Science and Engineering >Volume 8 >Issue 2 >Page 02000e13 > Article

High Power Laser Science and Engineering
Vol. 8, Issue 2, 02000e13 (2020)

Thermal lens analysis in a diode-pumped 10 Hz 100 mJ Yb:YAG amplifier

Victor Hariton^1、*, Celso Paiva Jo?o¹, Hugo Pires¹, Mario Galletti², and Gon?alo Figueira¹

Author Affiliations

¹GoLP/Instituto de Plasmas e Fus?o Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais,1049-001Lisbon, Portugal

²GoLP/Instituto de Plasmas e Fus?o Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais,1049-001Lisbon, Portugal

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DOI: 10.1017/hpl.2020.11 Cite this Article Set citation alerts

Victor Hariton, Celso Paiva Jo?o, Hugo Pires, Mario Galletti, Gon?alo Figueira. Thermal lens analysis in a diode-pumped 10 Hz 100 mJ Yb:YAG amplifier[J]. High Power Laser Science and Engineering, 2020, 8(2): 02000e13 Copy Citation Text

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Abstract

We address the power scaling issue in end-pumped laser rod amplifiers by studying, experimentally and numerically, the magnitude of thermal lensing in a high-energy diode-pumped Yb:YAG crystal. The spatio-temporal temperature profile of the gain medium and the focal length of the induced thermal lens are determined numerically. The influence of the repetition rate and pumping power on the temperature distribution is analyzed. Experimental measurements covered repetition rates between 1 and 10 Hz and up to 4 kW pumping power.

Keywords

diode-pumped lasers high-energy laser amplifiers thermal effects in lasers ytterbium-doped laser media

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$$\begin{eqnarray}S(r,z,t)=\frac{\unicode[STIX]{x1D702}_{s}P(t)}{w_{p}^{2}\unicode[STIX]{x1D70B}}e^{-1/2(r^{2}/w_{p}^{2})^{4}}\unicode[STIX]{x1D6FE}e^{-\unicode[STIX]{x1D6FE}z},\end{eqnarray}$$

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