采用OPA产生的中心波长为1.2759μm、平均输出功率为30mW、重复频率为250kHz、脉冲宽度为250
fs的光脉冲作为泵浦源,研究了PCF输出光谱随泵浦焦点与光纤端面的相对移动的光谱演变.在纤芯直径为2.0μm、长度为1.8m的光子晶体光纤中获得了近700nm的光谱展宽,展宽的光谱从1.09μm到1.79
μm,分析认为是高阶孤子的分裂和四波混频导致的光谱展宽,而在1.4μm左右的光谱凹陷是由于光纤中OH离子的吸收造成的.PCF输出的光谱可应用在WDM通信和光互连网的超短脉冲多通道光源中.

Supercontinuum with a spectral bandwidth of 700 nm (1.09μm ～ 1.79μm) was achieved in a 1.8-m-long photonic crystal fiber with an average core radius of 2.0 μm pumped by optical femtosecond pulses at the wavelength of 1. 2759 μm, with the average power of 30 mW, the duration of 250 fs and the repetition rate of 250 kHz from an optical parametric amplifier. It was interpreted that the spectral broadening was due to the fission of higher-order solitons and four-wave mixing. The concave profile at the wavelength of about 1.4 μm was resulted from the OH absorption. The broadened spectra were applicable to a multi channel optical source with ultra-short pulsewidth for WDM communication and photonic network systems.