We investigate the high-power durability of fiber Bragg gratings written directly into an ytterbium-doped large mode area fiber using ultrashort laser pulses. The gratings were successfully integrated as a high reflector into an oscillator setup reaching up to 1.9 kW signal output power with an efficiency of 87%. Defect states induced during the inscription process could be drastically reduced by a self-annealing process resulting in a stable laser performance.

中文翻译：

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飞秒写入光纤Bra布拉格光纤光栅，用于千瓦级光纤激光器

我们研究了使用超短激光脉冲将光纤布拉格光栅的高功率耐久性直接写入掺do的大模面积光纤中。光栅已成功地作为高反射镜集成到振荡器装置中，以高达87％的效率实现了高达1.9 kW的信号输出功率。铭刻过程中引起的缺陷状态可以通过自退火过程大大降低，从而获得稳定的激光性能。