In this letter, we propose a parallel dual-wavelength pumping (DWP) method (655 nm + 1981 nm) to realize high power output from a Er3+-doped ZrF4 fiber laser at ~ 3.5 μm, for the first time, to the best of our knowledge. This laser can emit a maximum power of 1.72 W, where the slope efficiency with respect to the launched 1981 nm pump is 31.5%. Further power scaling is mainly limited by the available 1981 nm pump power. Direct comparison with the common cascade DWP method (976 nm + 1981 nm) is performed. The results indicate that the parallel DWP method allows a larger output power at a certain 1981 nm pump power, thus providing another promising way for power scaling at this band.

中文翻译：

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采用 655 和 1981 nm 双波长泵浦的瓦级 ~3.5 渭m 掺铒钛 ZrF 钪光纤激光器


在这封信中，我们提出了一种并行双波长泵浦（DWP）方法（655 nm + 1981 nm），首次实现了约 3.5 μm 的 Er3+ 掺杂 ZrF4 光纤激光器的高功率输出。我们的知识。该激光器可发射最大功率为 1.72 W，相对于已推出的 1981 nm 泵浦的斜率效率为 31.5%。进一步的功率缩放主要受到可用的 1981 nm 泵浦功率的限制。与常见的级联 DWP 方法（976 nm + 1981 nm）进行直接比较。结果表明，并行 DWP 方法可以在一定的 1981 nm 泵浦功率下实现更大的输出功率，从而为该频段的功率缩放提供了另一种有前景的方法。