设计并研制了一种结构紧凑的高功率超连续光源。利用1.5 m掺Yb3+双包层结构大模场面积光子晶体光纤作为激光增益介质, 0°光纤端面作为一端腔镜和耦合输出, 半导体可饱和吸收镜作为另一端腔镜并启动和稳定锁模, 利用光栅对进行腔内色散补偿, 搭建了高功率抽运源, 输出平均功率1.5 W, 脉冲宽度494 fs, 重复频率55 MHz。系统分析了腔内动力学过程, 阐明了这种激光器的锁模运作机理。抽运1 m长光子晶体光纤, 产生了超过一个倍频程的超平坦超连续光谱(680～1450 nm), 输出功率500 mW。

A compact high power supercontinuum source is designed and explored. A 1.5 m Yb-doped double cladding large-mode area photonic crystal fiber is employed as gain media of the laser. 0° end face of the fiber serves as a cavity mirror and output coupler. Stable mode-locking is obtained by using a semiconductor saturable absorber as another cavity mirror. A pair of grating is used for intra-cavity dispersion compensation. As a pump source, the laser generates 1.5 W, 494 fs pulses at 55 MHz repetition rate. Systemic study of the dynamics in the laser cavity is presented. Mode locking mechanism of the laser is demonstrated. Over an octave (680～1450 nm) ultra-flat supercontinuum with an average power of 500 mW is generated in a 1 m photonic crystal fiber.