双零色散光子晶体光纤中可见光超连续谱的产生

摘要

在掺镱锁模光纤激光器发出的皮秒脉冲的抽运下，本文报道了双零色散的多芯光子晶体光纤中可见光超连续谱的产生。这种光子晶体光纤的类似同轴双芯结构提供了相隔很近的双零色散点。第二个零色散波长的存在阻止了反常色散区内的由脉冲内拉曼散射引起的孤子的频移，形成了稳态孤子，在短波长和长波长方向上的正常色散区均产生了可观的色散波。在2 W的平均功率下得到了550 nm到1700 nm的超连续谱。此外，光纤的同轴双芯特性也导致了入射脉冲的模式转换。实验结果和数值计算十分符合。%We report the visible supercontinuum (SC) generation in the double zero dispersion multi-core photonic crystal fiber (PCF), pumped by picosecond pulses from Yb-doped fiber laser. Such a dual-concentric-core-like PCF provides two closely spaced zero-dispersion wavelengths (ZDW). The redshift solitons will be canceled out at the vicinity of the second ZDW, and the steady solitons will cause considerable dispersive waves at the edges of the output SC which spans from 550 to 1700 nm at an average pump power 1 W. Moreover, the optical field is transferred from the inner core to the outer core. Experimental results agree well with the theoretical calculations.