Growth, Structure, Spectroscopy, and Laser Operation of a “Mixed” Yb:(Y,Lu)<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> Garnet Crystal
oleh: Sami Slimi, Pavel Loiko, Mingyan Pan, Pauline Lehoux, Venkatesan Jambunathan, Martin Smrz, Tomas Mocek, Yicheng Wang, Weidong Chen, Valentin Petrov, Rosa Maria Solé, Magdalena Aguiló, Francesc Díaz, Patrice Camy, Xavier Mateos
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2023-11-01 |
Deskripsi
A single crystal of ytterbium-doped “mixed” yttrium–lutetium aluminum garnet with a stoichiometric composition of (Y<sub>0.601</sub>Lu<sub>0.233</sub>Yb<sub>0.166</sub>)<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> was grown by the Czochralski method and its structure, vibronic, spectroscopic, and laser properties were studied. The stimulated-emission cross-section for Yb<sup>3+</sup> ions was maximized to 2.53 × 10<sup>−20</sup> cm<sup>2</sup> at 1031 nm. The emission bandwidth was ~8 nm, and the reabsorption-free luminescence lifetime of the <sup>2</sup>F<sub>5/2</sub> state was 1.063 ms. Pumped at 941 nm, the Yb laser generated a maximum output power of 1.04 W at 1.03 and 1.05 μm with a high slope efficiency of 76.4% and a laser threshold of 76 mW. A continuous wavelength tuning over a range of 51.6 nm (1026.4–1078.0 nm) was also achieved. Power scaling was achieved using a 969 nm diode-pumped microchip cavity. A maximum output power of ~9 W was obtained at 1.05 μm with a slope efficiency of 76% and an almost circular laser beam profile.