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arXiv · 2511.05235

Resonantly Pumped Tunable Tm,X:CaF2 Lasers: Effect of Buffer Ions (X = Y, La, Gd, and Lu)

Dominika Popelová·Karel Veselský·Pavel Loiko·Abdelmjid Benayad·Alain Braud·Patrice Camy·Jan Šulc·Helena Jelínková
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Abstract

We report on the eye-safe laser performance of Tm3+-doped calcium fluoride crystals, modified with optically inactive "buffer" cations (Y3+, Lu3+, Gd3+, and La3+), under in-band diode-pumping at 1.68 um. In the free-running regime, the 1.5 at.% Tm, 4 at.% Y:CaF2 laser operates with a high slope efficiency of 47% with respect to absorbed pump power. By employing an MgF2 birefringent plate, the emission wavelength of this laser is continuously tuned over 242 nm (1820 - 2062 nm) highlighting its potential for broadly tunable and ultrafast oscillators. The spectroscopic properties of Tm3+ ions in CaF2 crystals with and without buffer ions are also compared.

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Dominika Popelová, Karel Veselský, Pavel Loiko, Abdelmjid Benayad, Alain Braud, Patrice Camy, Jan Šulc, Helena Jelínková. 2025-11-07. Resonantly Pumped Tunable Tm,X:CaF2 Lasers: Effect of Buffer Ions (X = Y, La, Gd, and Lu). https://arxiv.org/abs/2511.05235

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