Ayevi Berke, Morova Yagız, Tonelli Mauro, Sennaroglu Alphan
Opt Lett. 2024 Feb 15;49(4):1017-1020. doi: 10.1364/OL.515648.
We report, for the first time to our knowledge, a demonstration of robust waveguide lasing near 2.7-2.8 µm in an erbium-doped fluoride host. Femtosecond laser inscription was employed to fabricate 50- and 70-µm diameter channeled waveguides inside an Er:YLiF crystal. The best power performance was obtained with the 70-µm diameter waveguide and 16% transmitting output coupler. The propagation loss and refractive index contrast were measured as 0.23 dB/cm and 7.1 × 10, respectively, for the 70-µm diameter waveguide. Both self-Q-switched (SQS) and continuous-wave (CW) operations could be obtained. During the SQS operation, as short as 240-ns pulses with average power of 51 mW, repetition rate of 368 kHz, and power slope efficiency of 15.2% were generated at the wavelength of 2717 nm with 465 mW of the pump power. During the CW operation, as high as 66 mW of output power was achieved at 2808 nm by using 460 mW of pump power at 798 nm, with a power slope efficiency of 19.6%.
据我们所知，我们首次报道了在掺铒氟化物基质中实现了近2.7 - 2.8微米的稳健波导激光发射。采用飞秒激光写入技术在Er:YLiF晶体内部制作了直径为50微米和70微米的通道波导。直径为70微米的波导与16%透过率的输出耦合器相结合，获得了最佳的功率性能。对于直径为70微米的波导，测量得到的传播损耗和折射率对比度分别为0.23 dB/cm和7.1×10。该波导能够实现自调Q（SQS）和连续波（CW）两种工作模式。在SQS工作模式下，泵浦功率为465毫瓦时，在波长2717纳米处产生了脉宽短至240纳秒、平均功率为51毫瓦、重复频率为368千赫兹且功率斜率效率为15.2%的脉冲。在CW工作模式下，使用798纳米处460毫瓦的泵浦功率，在2808纳米处实现了高达66毫瓦的输出功率，功率斜率效率为19.6%。
