摘要
目前产生超连续谱大多采用全内反射光子晶体光纤,光谱宽度达两个倍频程,但无法对其位置和宽度进行主动控制。全固态光子带隙光纤的带隙效应具有光谱滤波功能,通过设计全固态光子带隙光纤的带隙和带隙内色散特性,可产生特定范围内的超连续谱输出,同时色散特性受纤芯直径影响很小,有利于光谱可控的大功率超连续谱产生。根据1.064μm的抽运脉冲激光的需要,设计了全固态光子带隙光纤,并计算了第一带隙内的色散、损耗及非线性系数等参数。通过与波长有关的损耗将带隙效应引入到广义非线性薛定谔方程中,模拟了飞秒脉冲在全固态光子带隙光纤中传输的时域和频谱演化,得到带隙内超连续谱输出。比较了在有无带隙的情况下,飞秒脉冲的时域和频谱在带隙光纤中随传输距离的演化,分析了带隙效应对超连续谱产生的影响。
Recently, total internal reflection photonic crystal fibers are widely used in most supercontinuum generation, but the output spectra cannot be actively controlled. All-solid photonic bandgap fibers （AS-PBGF） with proper bandgap and dispersion can also be used for supercontinuum generation. The scheme is a candidate for controlling the range of supercontinuum generation because AS-PBGF can work as a filter, moreover, AS-PBGF is in favor of controllable high power supercontinuum generation because the core diameter has little influence on dispersion. The AS-PBGF used for supercontinuum generation with a pulse laser at 1.064 μm is designed, and its group-velocity dispersion, loss and nonlinear coefficient are calculated according to the structure and material parameters. The bandgap is included in the generalized non linear Schrdinger equation （GNLSE） through the loss dependent on wavelengths. The temporal and spectral evolutions of femtosecond pulse in the first bandgap are gained by solving the GNLSE using split-step Fourier method. The effect of the bandgap on the spectra extension is analyzed by comparing the output with bandgap and the one without bandgap.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2010年第9期2513-2518,共6页
Acta Optica Sinica
基金
教育部新世纪优秀人才支持计划(NCET-08-0142)资助课题
关键词
非线性光学
超连续谱产生
飞秒脉冲
全固态光子带隙光纤
nonlinear optics
supercontinuum generation
femtosecond pulse
all-solid photonic bandgap fibers
