Liu Lai, Qin Guanshi, Tian Qijun, Zhao Dan, Qin Weiping
State Key Laboratory on Integrated Opto-electronics, College of Electronic Science & Engineering, Jilin University, Changchun 130012, China.
Opt Express. 2011 May 23;19(11):10041-8. doi: 10.1364/OE.19.010041.
We numerically investigate mid-infrared supercontinuum generation in single mode fluoride fiber pumped by 1.56 μm picosecond fiber lasers. To get high energy conversion efficiency in mid-infrared region, the ratio of power generated in 2.5 ~5 μm range to the total input power for supercontinuum generation is optimized by varying the pulse width, peak power and fiber length. The long wavelength edge of the supercontinuum spectrum can be extended to 4.8 μm in a 100 cm long fluoride fiber pumped by a 1.56 μm fiber laser with a pulse width of 4 ps and a peak power of 100 kW, and the corresponding ratio of power generated in 2.5 ~5 μm range to the total input power is about 44.6%. The spectral broadening is mainly caused by self-phase modulation, stimulated Raman scattering and four-wave mixing. The simulated results show that high average power supercontinuum light source in 2.5 ~5 μm range could be obtained in fluoride fibers pumped by 1.56 μm picosecond fiber lasers.
我们对由1.56μm皮秒光纤激光器泵浦的单模氟化物光纤中的中红外超连续谱产生进行了数值研究。为了在中红外区域获得高能量转换效率，通过改变脉冲宽度、峰值功率和光纤长度，优化了在2.55μm范围内产生的功率与超连续谱产生的总输入功率之比。在由脉冲宽度为4ps、峰值功率为100kW的1.56μm光纤激光器泵浦的100cm长氟化物光纤中，超连续谱的长波长边缘可扩展至4.8μm，并且在2.55μm范围内产生的功率与总输入功率的相应比值约为44.6%。光谱展宽主要由自相位调制、受激拉曼散射和四波混频引起。模拟结果表明，在由1.56μm皮秒光纤激光器泵浦的氟化物光纤中可获得2.5~5μm范围内的高平均功率超连续谱光源。
