Here, a diode‐pumped laser based on trivalent terbium (Tb³⁺) as the active ion is reported. Optical pumping of a Tb³⁺‐doped lithium‐lutetium‐fluoride (LiLuF₄) crystal with up to 200 mW from a diode laser emitting at a wavelength of 488.2 nm enables continuous‐wave lasing directly in the green and in the yellow. At an emission wavelength of 542 nm, the laser reaches an output power of up to 43.8 mW with a high slope efficiency of 52% with respect to the absorbed pump power. The yellow laser at 587 nm exhibits a slope efficiency of 22% and the output power of 13.8 mW is only limited by the available pump power. Laser thresholds as low as 14 and 27 mW of absorbed pump power are observed for the green and yellow, respectively. The investigations toward further optimization of the laser performance reveal that highly Tb³⁺‐doped materials are suitable for compact, efficient, and affordable diode‐pumped solid‐state lasers with direct emission in the visible spectral range. These results are of high relevance, as in particular for the yellow spectral range such systems are currently not available.

中文翻译：

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Tb3 +：LiLuF4在绿色和黄色光谱范围内的二极管泵浦激光操作

此处报道了一种以三价ter（Tb ³⁺）作为活性离子的二极管泵浦激光器。掺有Tb ³⁺的氟化锂lut氟化物（LiLuF ₄）来自二极管激光器的200mW的晶体以488.2 nm的波长发射，可以直接在绿色和黄色中连续发射激光。在542 nm的发射波长下，激光达到高达43.8 mW的输出功率，相对于吸收的泵浦功率，斜率达到52％。587 nm处的黄色激光器的斜率效率为22％，13.8 mW的输出功率仅受可用泵浦功率的限制。对于绿色和黄色，分别观察到吸收泵浦功率的激光阈值低至14和27 mW。进一步优化激光性能的研究表明，高Tb ³⁺掺杂的材料适用于在可见光谱范围内直接发射的紧凑，高效且价格合理的二极管泵浦固态激光器。这些结果具有高度相关性，特别是对于黄色光谱范围而言，此类系统目前尚不可用。