Abstract Lasers based on erbium ions using 4I11/2 ​→ ​4I13/2 transition can generate laser radiation in the spectral range from 2.7 ​μm to 3 ​μm. Since the strong absorption peak of water is located at 3 ​μm, there has been an effort to develop a suitable laser source for various medical applications, e.g. dentistry, dermatology, urology, or surgery. Laser radiation from this wavelength range can also be used in spectroscopy, as a pumping source for optical parametric oscillators, or for further mid-infrared conversion. This paper represents an overview of the erbium-doped active media (e.g. Er:YAG, Er:YAP, Er:GGG, Er:SrF2, Er:YLF, Er:Y2O3, Er:KYW, etc.) for laser radiation generation in the spectral range 2.7–3 ​μm. In the first part of this paper, the particular active media are discussed in detail. On the other hand, the experimental results summarized absorption and emission cross-section spectra together with decay times at upper (4I11/2) and lower (4I13/2) laser levels of all tested Er-doped samples at room temperature. Moreover, laser results in CW and pulsed laser regime with tunability curves, achieved in recent years, are presented, too.

中文翻译：

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用于 ~ 3 μ m 二极管泵浦激光器的掺铒晶体活性介质

摘要 基于铒离子的激光器使用 4I11/2 → 4I13/2 跃迁可以产生光谱范围为 2.7 μm 到 3 μm 的激光辐射。由于水的强吸收峰位于 3 μm，因此一直致力于开发适用于各种医疗应用的激光源，例如牙科、皮肤科、泌尿科或外科。该波长范围的激光辐射也可用于光谱学，作为光学参量振荡器的泵浦源，或用于进一步的中红外转换。本文概述了用于激光辐射生成的掺铒活性介质（例如 Er:YAG、Er:YAP、Er:GGG、Er:SrF2、Er:YLF、Er:Y2O3、Er:KYW 等）。光谱范围 2.7–3 μm。在本文的第一部分，详细讨论了特定的活动媒体。另一方面，实验结果总结了室温下所有测试的掺铒样品的吸收和发射截面光谱以及上 (4I11/2) 和下 (4I13/2) 激光水平的衰减时间。此外，还介绍了近年来获得的具有可调谐曲线的连续波和脉冲激光状态的激光结果。