摘要
通过研究飞秒脉冲在双折射光子晶体光纤反常色散区传输时的偏振特性及对超连续谱展宽的影响,发现在偏振方向与光纤快轴或慢轴重合时,其输出的超连续谱具很好的线偏振.当偏振方向与快轴夹角为45°时,其输出基本上是圆偏振.由于高的双折射光子晶体光纤有高的非线性和三阶色散,所以可产生高偏振性的超连续谱.脉冲偏振方向与光纤快轴不同夹角的情况下,光谱成有规律的变化,当角度越接近45°时,光谱越平坦.高非线性光子晶体光纤可以产生很好的线偏振超连续谱.
It is investigated the propagation of femtosecond pulses in the anomalous dispersion region of a birefregent photonic crystal fiber and the effect of its polarization on the broadening of the generated supercontinuum.It is found that the generated supercontinum exhibits a good linear polarization when the femtosecond pulse is coupled into the fiber with its polarization along the fast or slow axis of the photonic crystal fiber.When the angle between the polarization of the input femtosecond pulse and the fast axis is equal to 45 degree,the output supercontinum is circularly polarized.Since photonic crystal fibers with large birefringence usually possess high nonlinearity and third-order dispersion,they can be employed to produce supercontinuum with good polarization.The spectrum of supercontinum changes regularly when the angle between the pulse polarization and the fast aixs of the photonic crystal fiber is varied.A flat spectrum is observed when the angle is close to 45 degree.The experimental observations indicate that solid-core photonic crystal fibers with large birefregent can be used to generate supercontinuum with good linear polarization.
出处
《华南师范大学学报（自然科学版）》
CAS
北大核心
2011年第2期65-69,共5页
Journal of South China Normal University(Natural Science Edition)
基金
国家自然科学基金项目(10974060)
关键词
飞秒激光
光子晶体光纤
超连续谱
偏振
femtosecond laser pulse
photonic crystal fiber
supercontinuum
polarization
