In this letter, we demonstrated efficient $\sim 2.9~\mu \text{m}$ lasing in Ho³⁺ /Pr³⁺ co-doped AlF₃ based glass fibers. The Ho³⁺/Pr³⁺ co-doped fibers were fabricated by using a rod-in-tube method based on the AlF₃- BaF₂- YF₃ - MgF₂- PbF₂ glass. By using a 50 cm long Ho³⁺/Pr³⁺ co-doped AlF₃ based glass fiber as the gain medium and an 1120 nm fiber laser as the pump source, lasing at 2868 nm was obtained, the obtained maximum unsaturated power was about 189 mW for a launched pump power of ~1.28 W, and the corresponding slope efficiency was ~15.3%, which was three times as high as that derived from singly Ho³⁺-doped AlF₃ based glass fibers. Our results indicated that Ho³⁺ /Pr³⁺ co-doped AlF₃ based glass fibers were promising gain media for constructing efficient $\sim 2.9~\mu \text{m}$ fiber lasers.

中文翻译：

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Ho3+/Pr3+ 共掺杂 AlF3 基玻璃纤维，用于高效 ~2.9 μm 激光器

在这封信中，我们展示了高效 $\sim 2.9~\mu \text{m}$ 在基于 Ho ³⁺ /Pr ³⁺共掺杂 AlF ₃的玻璃纤维中进行激光发射。Ho ³⁺ /Pr ³⁺共掺杂光纤是基于AlF ₃ - BaF ₂ - YF ₃ - MgF ₂ - PbF ₂玻璃采用管中棒法制备的。通过使用 50 cm 长的 Ho ³⁺ /Pr ³⁺共掺杂 AlF ₃以玻璃纤维为增益介质，1120 nm 光纤激光器作为泵浦源，获得 2868 nm 的激光，在发射泵浦功率约 1.28 W 时，获得的最大不饱和功率约为 189 mW，相应的斜率效率为~15.3%，是单一 Ho ³⁺掺杂的 AlF ₃基玻璃纤维的三倍。我们的结果表明，Ho ³⁺ /Pr ³⁺共掺杂AlF ₃基玻璃纤维是一种很有前途的增益介质，可用于构建高效的增益介质。 $\sim 2.9~\mu \text{m}$ 光纤激光器。