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arXiv · 2506.08948

A study of cross-relaxation and temporal dynamics of lasing at 2 microns in Thulium doped ceramic

Alessandro Fregosi·Fernando Brandi·Luca Labate·Federica Baffigi·Gianluca Cellamare·Mohamed Ezzat·Daniele Palla·Guido Toci·Alex Whitehead·Leonida A. Gizzi
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Abstract

We report the characterization of the pump absorption and emission dynamic properties of a \tulio{} ceramic lasing medium using a three mirrors folded laser cavity. We measured a slope efficiency of 73\%, which allowed us to retrieve the cross-relaxation coefficient. The behavior of our system was modeled via a set of macroscopic rate equations in both the quasi continuous wave and the pulsed pumping regime. Numerical solutions were obtained, showing a good agreement with the experimental findings. The numerical solution also yielded a cross-relaxation coefficient in very good agreement with the measured one, showing that the cross-relaxation phenomenon approaches the maximum theoretical efficiency.

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Alessandro Fregosi, Fernando Brandi, Luca Labate, Federica Baffigi, Gianluca Cellamare, Mohamed Ezzat, Daniele Palla, Guido Toci, Alex Whitehead, Leonida A. Gizzi. 2025-06-10. A study of cross-relaxation and temporal dynamics of lasing at 2 microns in Thulium doped ceramic. https://arxiv.org/abs/2506.08948

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